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Discussion Starter #1
I figured I should start a tread on my 4bt swap round 2. I first started out with a 4bt with a 700R4. Worked fine but the 4bt would crack the torque converters. I broke 2. I have also tried different stall speeds. I am going to just try and summarize some information for everyone in hopes that it will help others to learn from my mistakes.

1. Do not use the 700R4. Tranny may take it if it is built VERY strong but I kept cracking torque converters. Use a manual transmission or some stronger automatic. I think bolt action is by far the simplest and easiest. I did not want to go to a manual as my truck was a automatic truck to start with. I am happy with the 4L80E so far.
2. Use a ~1500 Stall converter. 1200 is too low. The low stall makes the motor shake when in gear at a stop. The low stall makes it hard for the motor to build boost and make power for crawling or lugging up a hill or anything for low speed steep inclines. 1500 Stall makes good boost and no power issues at low speeds/inclines. You will be able to burn rubber if you wish.
3. use fluid filled motor mounts. This makes a HUGE difference in engine vibrations. when you start your project just buy the good fluid mounts and build your mounts around them. DO NOT USE the solid rubber motor mounts. they transmit many of the 4b's vibrations to the truck frame and make your mirrors shake and everything else. I hated my solid motor mounts.
4. Get a fluid damper. Its expensive but worth it. Again takes a lot of the 4b's vibrations out. Makes a huge difference.
5. If you rebuild your motor you MUST have the rotating assembly balanced. Its $200 bucks well spent. my motor was 14grams off. my flywheel/flex plate was 12Grams off. Again a vibration killer. Makes a big difference.
6. On my 4L80E I went the cheap route and got the TCI EZ TCU controller. I do not think this is the best. I am unhappy with the shifting of this controller. I would go with one that allows you to individually adjust shift speed and rpm for each gear. I am still currently fighting this controller trying to "tune" it.
7. Get a new turbo if you have the H1C. I went with the HX30W and am very happy. Huge low RPM power increase. Builds great boost and increases drivability.
8. Be very careful but get a pyrometer and install it before the turbo in the rear chamber of the exhaust manifold. I have been unable to find an definitive do not exceed this EGT but I use 1200 as my number. I will go to 1300 for a little bit but then back off. I installed a intercooler and that helped my EGT's stay lower.
9. Do not buy the "cheap" ebay starter. They do not last. your luck may vary.
10. Electric fans are fine. I have no issue with heat.
11. I was absolutely amazed at how the exhaust system transmitted vibrations to the body of the truck. I drove the truck around with just the down pipe attached and after I took it to the exhaust shop and had the muffler installed the truck rattled like crazy. Buy the wire mesh 8" flex pipe and install that close to the front as possible. This will eliminate the transmission of the vibrations to the rear part of the exhaust. This made a big difference.

I am still fighting my EGT's. I would like to lower them. I was thinking my intercooler would lower them but it just delayed the time to get to my max EGT.

I am still fighting my 4L80E controller. I wish it would shift better.

I guess that is enough for now. I will try and add photos and do more of a display of what I did. If anyone has some good advice on the tranny controller or how to lower my EGT's any info would be appreciated!
 

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Very good info here. You've had the real world experience and that's very important. You didn't mention which injection pump you have. Lowering your EGT's can take several routes. By the way 1200-1300 isn't excessive. First, where do you draw your air for the air filter? The cooler the intake air, the better. You have an IC so that's good. Second, how large is the exhaust? 3" is usually adequate. Third, what boost level are you seeing? If you're peaking out around 18 psi, you have room for a good bit more. More air burns the fuel better. Also, which HX30W do you have? Are your injectors stock? Also, have they been tested for pop pressure and spray pattern. Balanced injectors make the engine run much much better. Last, would be IP adjustments. If you haven't adjusted the timing from the stock setting, advance it a little and see the result. Advanced timing generally lowers EGT and improves fuel economy. Also, if the IP fuel has been turned up, might back it off just a tad and check the results. The info you've provided here is what people really need to know.
 

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Discussion Starter #3
I have the bosh VE pump. I turned the power screw 1 turn and rotated the pin 240 degrees so it ramps up fast. My air filter is away from the motor close to the battery in the corner of the engine bay. I know its not a "cold air" spot but that's what I have done so far. So improvement can be made with my air intake. My exhaust is 3 inch straight pipe all the way to the back of the truck. It is surprisingly not very loud. I see 22lbs boost at WOT. When I put the turbo on that is what it was set at and I have not changed anything. I am not sure what the exhaust and intake side are on the turbo if that is what your asking. My injectors are stock. I did not take them to the injection shop to have them tested. So I do not know the exact status of my injectors. I have not adjusted the timing on the injection pump. It is at the stock mark currently.

Overall I have been happy with the power output of the motor. It runs very smooth. I was wondering about messing with the injection pump timing. Should I have my injectors tested? I was also wondering with regards to EGT's if I should increase boost pressure.

Trying to see if photos work.
 

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Discussion Starter #4
OK I think I got photobucket working for images. I am going to start from the beginning as it may help others trying to plan their build. This may jump around a bit but I am trying to highlight some of the more interesting areas of the build.

Here is the motor with my new adapter plate installed. Fresh from the panel van. Wow first steps!

I then got my 700R4 in position in the truck and started fitting the motor in to build the motor mounts and cross member.



I then quickly found out the oil pan will hit the axle so I needed to modify that.



Got that out of the way then the oil pickup tube would not work. So then I ordered a 5.9 oil pickup tube and did some modifying so it would fit in the modified pan properly.


Once that was all installed and in place in the truck I had to figure out how to get the 700R4 TV cable to work properly so it would shift. I measured the geometry of the carb and fired up my 3D cad program. I then 3D printed the throttle linkage. A few modifications and I had it up and running.




Here it is in the truck Round 1...


With the stock 700R4 in there was not a lot of room for the down pipe on the exhaust.


Wow I thought things were going good. Until....


My torque converter cracked. Well I guess my stock 4bt had more power than I thought!

I then proceeded to get a new heavy duty version for the 700R4. This torque converter worked good. I started to play with the motor a little bit. I turned up the power screw 1 turn. I then turned the fuel pin so it would ramp up fuel faster. These adjustments made a huge improvement in power and drivability. I could actually hear the H1C turbo spool now.

I will upload some more photos and continue later.
 

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OK, more good info. You've adjusted the pump some for more power. I'd think a bit of timing advance would be in order. Do a little and see how it performs. You can always go back to the original setting if it doesn't work. I suspect it will make an improvement though. If you have the time and can live without it for a few hours, pull the injectors and take them to a shop for testing. If they are good then you're only out a few bucks. If they are out of adjustment or in need of replacement you need to know that before they become a bigger problem. Stock injectors for these engine aren't real expensive. You don't need bigger ones unless you're going crazy with the power. You're boost level tells that the waste gate is at stock setting. You definitely have room for improvement there and it will most likely help the EGT. You can either adjust the control arm to keep the gate closed longer or add a boost elbow in the air line to the actuator. The boost elbow lets you adjust the boost with a set screw instead of having to take anything off the turbo. It's just a tiny pressure regulator. The HX30W can easily do 30 psi. When I asked which HX30W you had, I was referring to the size of the compressor inducer. The basic unit found on the P pump 4bt is a 40 mm. There is a 44 mm and a 46 mm which is called the Super HX30W. The Super is easy to identify because it has a 4" air inlet instead of the 3" found on the other models. You mention that the exhaust is pretty quiet. The turbo muffles a lot of exhaust noise. Guys who run twins seldom need a muffler. If your 700R4 was built to handle the 4bt, you probably needed a billet converter to keep from breaking them. You saw what that low end torque can do.
 

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USShift transmission controller will do everything you are asking for. I'm running one on a 4L60e and it gets the job done.
 

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johnpp77, The website would not let me respond to the PM you sent but here are my thoughts.
johnpp77 said:
I think I have a very similar setup that you had or have. I have a 4bt in a 85 chevy with a 4L80E and have the TCI EZ TCU controller. I had the early dodge CPS with all black wires and did the pull up resistor etc. My tach in the truck was happy and my TCU controller seems to read properly. I supplied 12V to the CPS but now it quit. After some reading around it seems they were supplied 5 to 8V from the stock ECU. I think I must have fried my CPS or it is going bad. I adjusted the gap again and now the tach wiggles a bit but it will not give a constant signal. The tach goes from 0 to 700 RPM at idle and floats around so the signal is not consistent as it was before. This then throws off the TCU as it does not know RPM. Do I need to use 5 or 8V if I get a new CPS? I was using battery voltage which goes up to 14V. I wonder if this is making my existing CPS go bad. Your thoughts?
My thoughts are maybe it’s a connection issue on any of the wires on the CPS or an issue with the connection with the resistor. I soldered and used heat shrink on my CPS connections. I spaced mine around .020” from the dampner and I used 12 volts and it has been working great for over a year now.
At first I used the RPM signal conditioner but it caused the RPM not to be very accurate and I found that the trans did not shift correctly so I feel that that it does affect the controller below 80% throttle.
Problem 2.
Also my EZ TCU does not shift well from 1-2. It only shifts well if I go to WOT from a stop then everything shifts ok. If I accelerate from a stop using 50% throttle it will not shift into 2nd gear. Once I am above 2nd gear the others shift properly. TCI Tech support says that RPM is ignored at any throttle setting below 80%. I have not been able to "tune" this TCU. Any Ideas?
Thanks!!!
After the RPM is right and if the trans is still not shifting correctly I would check the TPS signal for accuracy with the engine killed. Then I would test drive it to see if under normal acceleration does the controller screen shows a command for a 1st to 2nd gear shift and is the TCU controller flashing any codes after driving it? If it is not flashing codes and it is giving a command to shift to second I would suspect something is wrong with the transmission internally with such as a solenoid or something sticking. If this is the case I would do a google search to find others with similar symptoms to see what the problem was.
 

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Discussion Starter #8
Char, I will advance the pump timing next a little bit. I have to pull the pump as my tappit cover gasket seems to have developed a small oil leak in the corrner. I ordered a new gasket and when I put the pump back on I will advance it a bit. Quite frustrating as one of the reasons I rebuilt the motor was to get rid of all the oil leaks. I was also thinking about getting one of those boost adjusters so I can up the boost a bit. I will take it up to 30 and see what happens.

Casey, Thanks for the controller advice. I will keep trying to make this one work properly but I have to get my RPM signal working properly again as my CPS went bad. I have to order a new one I think.

ShootRacing, Its not the tranny as tech support had me put it in manual mode and it shifts immediately when told up or down. The controller is not telling the tranny to shift from 1-2 shift when it should. Again I cannot say it is the control box yet as my RPM from the CPS is not correct now. I have to fix that first so I can trouble shoot more. Back when I sent the PM Everything was reading accurately then stopped that's why I was wondering if a full 12V would fry the CPS. I am going to order the 98 version like you have in hopes that it will work better.

I have some more photos uploaded and will have to continue my story when I have some more time. Thanks everyone!
 

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The tappet cover gasket is a notorious leak point. Just be sure both the block and cover surfaces are clean and torque the bolts to the correct specs.
 

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Discussion Starter #10
Well I am off today to get my new CPS sensor and gaskets as they have arrived at the parts store. This will allow me to get my RPM signal correct again hopefully getting my Transmission to shift properly. It will also let me fix my tappet cover leak that has been bothering me.

Ok back to the build story. After I cracked my torque Converter. See photo below. I had my tranny shop order a HD converter for the 700R4.

I got the new torque converter installed then I started on modifying my throttle linkage a bit to improve on the design. I added bearings to the main rotating linkage arm.



This helped with the overall smoothness of the throttle feel and also helped the 700 shift better. I was very happy with how this turned out.
I then had a friend CNC the part that connects to the front cover as it get very hot and would crack the plastic part. I then modified the arms for clearance and so here is a photo of the final product.

Now that I had my 700R4 working good and I was done messing around with my throttle linkage I then started to focus more on some upgrades! This is when I started to do a lot of home work on turbos. What started the turbo search was I was having strange blow by issues. My crank case seemed to get pressurized so one possibility could be the seals were out from the compressor side of the turbo leaking into the oil drain. I did have some oil circulation in the turbine housing so I started to look into rebuilding the turbo. I found some turbo center housings but they cost almost as much as a new turbo. I then decided to upgrade totally to the HX30W as it was the same money as the rebuild. I also ordered a pyrometer and boost gauge.


It did not take me long to install this upgrade as it was a direct bolt on unit. I had to tee in the boost line into the intake. I also found out that it moves the exhaust flange back towards the firewall 1/2" making the exhaust even harder to fit. So back to the exhaust shop for exhaust #2. One word of advice I could not get to all 4 of the turbo bolts to the exhaust manifold so I found it much easier to just remove the manifold, install the turbo, then reinstall the manifold on the motor. Photo of turbo removed trying to figure out how to get the new one to fit..... Hmmmm

Ah ha just remove the exhaust manifold then the new turbo will bold on fine and you can get to all 4 of the flange bolts.

I then discovered that you must "clock" the turbo housings so the oil and drain lines line up and the boost housings line up. This took a little bit of fine tuning to make sure everything was correct. Once that was installed my boos was at 22psi right out of the box. WOWOWOWOW what a difference this turbo made. Huge!!! It would build boost almost instantly and hold 22 psi through the RPM band. This was one of the biggest increases in drivability I did to the motor. Now I was getting very close to being happy with this swap in power terms and drivability. Before it was a total dog off the line. So now that I had a pyrometer and a boost gage I thought it was time to turn the fuel screw. So after snapping the lock collar off the screw I then turned it in 1 turn. Again WOW that made a big difference! Just watch your EGT's if you start messing with the power settings on the injection pump. I then turned my fuel pin so it would ramp up faster. This made a difference in the off the line acceleration. It also made the truck make a single puff of black smoke when you floored it then cleaned up instantly. This is where the motor is currently and I have not messed with it since. I figured if I turned it up any more it would tear out my 700R4 tranny as it is the weakest link. I then preceded to drive it this way for about 4000 Miles and was very happy with the truck. I never did get rid of the weird blow by issues the motor was having. Good power and about 21 to 19 MPG in a square body Chevy with Dana 60 axles front and rear with 4.56 Gears. It was a big step up form the 350 gasser at 6 to 8 MPG normal. The best I got with the 350 was 10MPG.

Ok I have more story to write but I can only post 10 photos per post.
 

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Discussion Starter #12
Big Red, I am not sure what transmission you plan on using but I would not recommend 700R4 transmission or anything weaker. I have not finished my write up about what I have done so far to my truck but I no longer use a 700R4. I switched to the 4L80E as I have broke 2 torque converters with the 4bt. The first cracked the input housing the second was a HD unit and it broke off one of the 3 mounting pads to the flywheel. Too much torque pulsing for 3 bolts. The 4L80E has 6 bolts on the torque converter. You might want to look into a billet style torque converter with 6 mounting holes for your tranny. I know some of the trucks had a turbo 400 with 3 mounting bolts but they had some sort of wave ring in the stock setup. This wave ring in my opinion would adsorb some of the jarring of the 4bt torque pulses and keep the torque converter from breaking as it was insulated from being directly bolted to the motor. Again I am not 100% sure that was the intended purpose of the wave ring in the stock setup but it seems to make since to me with my experience. Anyway just my $0.02.
 

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Discussion Starter #14
OK back to my build. I had this sneaky feeling that my 700R4 was going to go out on me based on other peoples posts on this site so I started to gather parts to move into a stronger transmission. I chose a 4L80E. I picked up one from a local junkyard and took it to my tranny shop for a good look over. I ordered a 1500 Stall torque converter this time and now that it is in the truck I like the 1500 stall much better than the 1200 stall. I ordered the TCI EZ TCU tranny controller. I also ordered a intercooler. I found out that my NP 208 transfercase would directly bolt on to my 4L80E transmission out of a 95 Chevy truck with its stock transfercase mount. I just had to switch the input on the NP208 from the 27 Spline Turbo350/700R4 to the 32 spline of the Turbo400/4L80E. Wow something easy for a change! So now with all the parts here my 700R4 died for the second time breaking one of the 3 mounting pads to the flexplate. I was so mad that I did not bother taking photos of the broken torque converter. I then had to get some time to switch out my 700R4 for the 4L80E. This was going to be a big project as something has to move. Either the motor has to move ahead and the motor mounts have to be remade, etc, etc. or the motor stays put and the crossmember moved and driveshaft's cut and changed. I decided to keep my driveshafts stock and keep my transfer case mounting in the same location as stock. This did move the crossmember slightly further ahead. It also moved the motor ahead as well. Now that I had everything out of the truck again I did not want to do this again so I decided to rebuild the motor. Wow its amazing how one thing leads to another.... It is always more $$$. Here is the motor out of the truck.

So now for motor tear down.
Not exactly knowing what I was doing I marked the timing gears at TDC so I could put it back together the way it came apart. (It proved a good idea later in assembly as my pump gear did not have any timing marks!)

I was surprised the cylinders looked good.

Head seemed good too. So once the motor was all the way apart everything went to the to machine shop for inspection.

The machine shop found out my head was cracked in 3 cylinders so it was junk.... :(


So I had to find a new cylinder head. Man was I not happy about that. More $$ out the door. I was beginning to wonder what I got my self into. My "easy and cheap" swap was quickly turning into a complete nightmare. By the way there is no such thing as a "easy and cheap" engine swap. It just does not exist!! Well I started to look at this project as a learning curve project. I thought about finding another complete motor and starting over or just giving up. After a good nights rest and some time for things to sink in I decided to find a new head and finish my rebuild so I know exactly what I have. To my surprise a complete new cylinder head is not very expensive at all. I could not believe it. The rebuild kit was cheaper than I thought as well. My cylinder block needed to be decked 0.010 to clean it up but my cylinders were just honed and I could use my original pistons. Good news as that saves some cash.

I got my block back from the shop!

I cleaned it up and started assembly. I just followed the procedure in the Cummins repair manual. Very easy to follow and its step by step.

Another word of advice order new head bolts and rod bolts right away with your motor kit. My rod bolts would not take final torque. I reused my main cap bolts only. After the cam and lifters are in you can rotate the motor over. It makes the cam and tappets easier to install upside down with the oil pan up.


Have to stop here no more photos in one post.
 

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Discussion Starter #15 (Edited)
I then gave it a bit of a paint job before I finished installing the other items.



I then installed the injection pump.

Good thing I marked the gears when I took it apart as I did not have to figure out how the gear should be orientated. (Pat on back!) ;)
I then installed the new cylinder head after a good cleaning. EDIT: When I was going to install the cylinder head I noticed that the manual talked about x's on the side of the block indicating the decking of the block. I found 2 x's like this XX on the side of my block. My machine ship decked the block 0.010. This means that it has been decked 3 times. OH S%@!..... I had no idea what to do. My head gasket was for a 10 thousandths. They do not make a 30 Thousandths head gasket. I was planning to disassemble the bottom end again and take 10 off the pistons. I then found a section that says to measure the piston protrusion from the deck and then measure the valve recession from the firing plane of the head. May luck be with me I was barely with in spec. using a 0.020 head gasket. So I continued with my build :EDIT


Then it got a good paint job.

Then everything else got installed.

Now that the motor was done I had to do some test fitting so I could make the new motor mounts. This time I used the fluid filled type to help minimize vibrations. One of my goals was to tame this 4bt down so it did not vibrate the truck. First I cut out the original mounts I built.
 

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Discussion Starter #16
I then started building new ones. First I had the tranny and transfercase installed where it needed to be. That set the location for the new motor mounts.



Here are the mounts with the motor installed.


The 4L80E gave me much more room at the rear of the motor. This made it much easier for the exhaust.

Final test fit.

I then wanted to polish my valve covers to make the motor look nice. Wow that took a while!

Ohhhh but they look good!!:beer:

Getting it ready for the first start.... Gee I sure hope I assembled it correctly.
 

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Discussion Starter #17
Well it did start right away after priming the pump a bit. It ran fine and built oil pressure right away. Wow was I happy there was no problems with the rebuild! Since I switched to the 4L80E transmission I needed RPM signal, TPS signal, and shaft output speed from the rear sensor in the transmission. The RPM signal I found some posts here that talked about how to use the CPS sensor to get a tach signal. http://www.4btswaps.com/forum/showthread.php?24625-how-to-get-your-tach-to-work-with-the-stock-12-valve-CPS-(crank-position-sensor) Using their method I rigged up a 1K Ohm resistor from the power wire to the signal wire on the CPS as a pull up resistor. This allowed the CPS to signal 12V signal to any standard tach. My fluidampr had 2 notches in it which gives 2 pulses per rev which converts to a 4cyl setting in the aftermarket tach. My transmission controller allows you to select how many cyl the motor is to get correct tach signal. I originally used the early version of the CPS with all black wires and one white wire. This was a little difficult to wire up. It only worked for 800 miles then it stopped reading correctly. I then purchased a newer version standard part number PC260. This one made the wiring easy as it is color coded. Red power, black ground, and white is signal. Do not forget to install a 1K pull up resistor between the Red and White wires. A little more difficult to figure out was the wiring for the TPS. I used a standard clock wise version of the easy to find chevy tps sensor and built a bracket to hold it in place. Here is how the wiring looks for the tps to the ez tcu controller.


This gives for 0V to 5V at WOT on the TPS. Now some advice on the TCI EZ TCU. It will always give a TPS error code in the computer if you do not have at least 0.4V at closed throttle position. So closed throttle needs to be 0.4V or higher. WOT does not need to be the full 5V spread of the TPS sensor. I started my Closed throttle position at 0.8V and WOT yields about 4V. The EZ TCI TCU has a calibrate TPS area and it reads minimum and maximum values of the TPS voltage and calibrates accordingly. Here is the bracket and peg I printed up to hold and operate the TPS sensor.



With that installed my Tranny computer had all the information it needed to operate the transmission. I am still messing with this computer trying to "tune" it better to my transmission.

I then added an intercooler and this is how it looks currently.

So far I have 1200Miles on it after the rebuild, reinstall and transmission upgrade.

Ok things I am working on yet
1. Transmission computer is not shifting from 1 to 2 like I think it should. ( this is a whole topic on its own).
2. I have to find my cruise control bracket from the vacuum diaphragm to the throttle linkage then my cruise will work.
3. I have to build a A/C pump mounting bracket so I can get the air working.
4. I have a tappit cover leak in the corner. Nothing serious but it makes me mad.... and it also has to be one of the hardest gaskets to get too. I have to remove the Injection pump and vacuum pump to get to it. I now have the new gaskets here so I just have to find some time to install them. My plan is to advance the injection pump a bit per advice when I assemble this back on the motor.
5. I have to move my intercooler lower in the radiator area as it interferes with the safety latch in the hood. I installed it too high so I had to remove the latch so it would not hit the top of the intercooler.
6. My gears are 4.56 Dana 60 axles and 32" Tires. I am way out of the RPM band for fuel economy. My 65MPH RPM is 2400. I think I should have this at 1900 RPM ish. This would mean I need to get 3.73 Gears or maybe better ~3.56 gears to get better RPM's. Maybe I needed the 6L80E LOL.

I am sure there is more but for now it is working and driving and I am happy with that. That is where I am currently. I hope this write up helps some others in their builds and planning decisions. If I missed something or an area needs more detail let me know and I can fill in what I forgot to write in. I may have put too many photos in but I think they help explain a lot. Thanks everyone for your help!
 

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You've covered everything very nicely. That throttle linkage is beautiful. I can understand the torque converters breaking if you only had the 3 stud version. When the TH475's were used in the delivery vans they had 6 stud. Are you using the factory wave ring? Those flex a bit much. Member RubeBonet makes a custom unit that replaces those and it won't flex. Member Oldroofer is using one. If you can get your cruise speed into the 1800-2000 rpm range your fuel mileage will improve considerably. On the ac pump, are you putting it on the driver's or passenger's side? Is it V belt or serpentine? If it's V belt, you can add an accessory pulley on the front of the fan hub to drive it. There are brackets available for GM vehicle from Auto World in Montana. http://www.cumminsdieselrepowers.com/ They specialize in GM conversion.
 

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Discussion Starter #19
OK sad day. Now my 4L80E started leaking oil around the torque converter. So I removed the transmission to see what went wrong. Once I had the tranny out I could not remove the torque converter from the tranny. It took a few pry bars but I got it off. The collar was locked on the torque converter input shaft. So my pump is shot. Now I have an issue. This is a total of 3 torque converter problems I have had. 2 cracked on for 700R4 (3 Stud versions) and now a 4L80E torque converter issue with the pump bearing collar seizing onto the converter. This makes me wonder if my adapter/flex plate is true.... I took a caliper and checked measurements through the flexplate holes to the adapter plate and it was all within a few thousandths. Seems fine. Maybe I should find a dial indicator and check the plate that way.

These problems with the trannys are very frustrating not to mention expensive. I sent the tranny computer in to be checked at TCI. Maybe the computers super hard shifting from 1 to 2 made this happen?.... I thought by switching to the 4L80E it would fix my transmission issues.
 

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I wonder if the thrust bearing has broken?? A crank moving back and forth. .would that cause the tc problems??
 
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