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Discussion Starter · #1 ·
Having problems shifting. To the point that by the time I get into 3rd gear, I'm at a rolling stop pace.

Low km tranny, new Amsoil 2000 fluid, new clutch, new flywheel, new pilotbearing. No luck.

Tried changing the the distance the slave moves, maybe the clutch was not fully disengaging, but no luck there. Not even better.

When I have the truck idling, and I shift into 5th, I have to shut the truck off to get it out of gear. Wouldn't come out even with the truck rolling.

2000 TJ, 4BT, NV4500. Stock slave and master.

-Scotty
 

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Is the gear shifter difficult to move? Or will it just not move to gear? Does it grind?

I'm thinking it's in the fluid. Even if the clutch was engaged you can shift w/o a clutch with the correct rpm's.

Have you tried using the OEM type GM-syncromesh fluid? My Pops put some 90W in his 4500 once and it wouldn't hardly shift, replaced with Syncromesh fluid (1992 C2500)
 

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Hey, you know, I have just started having the exact same problem! I have a HD dodge NV4500 with dodge slave cylinder. I have always used the OEM synthetic NV4500 oil straight from Dodge. I think maybe I'll check the oil level, I'll get back to you...
 

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I've been using Amsoil lube for 6 months, some slight problem with synchros on occasion. In my case I had fabbed my own slave pushrod and I'm pretty sure it needs to be longer. Amsoil says their lube is the same as the specified Meritor formula and a lot of guys have used with no problem. Also Amsoil specifically names Meritor formula and NV 4500 useage in the advertising so you can be pretty sure they covered all bases in regard to liabilities for transmission damage.

What bellhousing, flywheel, clutch/pressure plate are you using?

Did you use the needle-roller pilot bearing?

What clutch release arm and release bearing are you using?

Which clutch master and clutch slave are you using?

Are your master/slave hydraulic lines steel tubing or flexible/rubber?

Are you using the stock shifter or the 'short throw' aftermarket part?
 

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Having problems shifting. To the point that by the time I get into 3rd gear, I'm at a rolling stop pace.

Low km tranny, new Amsoil 2000 fluid, new clutch, new flywheel, new pilotbearing. No luck.

Tried changing the the distance the slave moves, maybe the clutch was not fully disengaging, but no luck there. Not even better.

When I have the truck idling, and I shift into 5th, I have to shut the truck off to get it out of gear. Wouldn't come out even with the truck rolling.

2000 TJ, 4BT, NV4500. Stock slave and master.

-Scotty
Hey Scotty,
Did you change the fluid, install a new clutch, flywheel and pilot bearing to try to fix the problem, or have you started with these parts and then found out that you have this problem? I seriously doubt that it is the fluid, as this will definitly not cause the hard to get out of fifth problem. Sounds to me like the clutch is not disengaging completely, or the input shaft is binding in the pilot bearing. I run Amsoil in my NV 4500, and the gear chatter under load is quieter than with the GM/Chrysler recommended Castrol Syntorq fluid.
Let us know what you find please.
Bob B.
 

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Scotty,
One more thing to check: Make sure your bellhousing alignment pins are in, and the mating holes are not worn. A problem in this area will cause the input shaft to bind in the pilot bearing, and also destroy the clutch disk.
Bob B.
 

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Having problems shifting. To the point that by the time I get into 3rd gear, I'm at a rolling stop pace.

Low km tranny, new Amsoil 2000 fluid, new clutch, new flywheel, new pilotbearing. No luck.

Tried changing the the distance the slave moves, maybe the clutch was not fully disengaging, but no luck there. Not even better.

When I have the truck idling, and I shift into 5th, I have to shut the truck off to get it out of gear. Wouldn't come out even with the truck rolling.

2000 TJ, 4BT, NV4500. Stock slave and master.

-Scotty
You say you changed the distance of the slave,what's does it do when you pump the clutch ped 5 or 6 times if it works and you can get it out of gear than you have a hyd problem * air or clutch master not having enough bore .

By changing the rod on the slave doesn't do anything but push the rod back into the slave ,what you need to do is change the rod lenght of the master ,the master tells the slave rod how far to move.You may have to go to a bigger bore on the master .

Hope that make since to you ,let us know .

Scott
 

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Scotty,
You shouldn't have very much freeplay in the pedal with a hydraulic clutch release system. You should start to feel the pressure plate spring pressure (resistance) after pushing the clutch pedal about an inch or 1.5 inches. Any more travel before you start to get resistance, and you've probably got air in the system.
Bob B.
 

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Discussion Starter · #10 ·
Master-line-slave is the stock TJ unit. It's all one piece and sealed so there's definately no air in it. It was simply moved out of the way during the swap and then reinstalled. Bolts right up. Using the dodge adapter plate, dodge flywheel, dodge clutch. Dodge throwout lever.

I'm not sure what pilot bearing they used but I can find out easily.

All of these parts were installed as part of my swap, and I feel the transmission is pretty tough to shift. It slides right into gear no problem first thing in the morning, but it seems once the fluid warms a bit, it gets hard to shift.

I talked to the guys who did my swap (both licensed HD mechanics) and they say it shifts normally, but I don't remember my friends 98 3500 Dodge shifting anywheres near this hard.

Hope I've covered everyone's questions. I'm a licensed mechanic as well, I just can't figure this out.... everything's new.
-Scott
 

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Seen the same exact symptoms in cummins dodges. It was the clutch itself. Faulty material in the disc or pressure plate and one or the other swells/distorts as you drive it and the parts heat up. Get's to a point where shifting is near impossible as the clutch won't disengage. When it does it, shift using the RPM's of the engine. Should shift fine that way and that will tell you for sure.

The alignment is something else to check
 

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Any possible chance that you could have installed the clutch disk backwards? Do you remember if it was marked "flywheel side" anywhere on the disk?
 

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Discussion Starter · #13 · (Edited)
As for changing the distance on the slave: The TJ comes with a plastic 3/16" spacer that clips to the mounting surface of the slave. I took that off to see if it made any difference (move the slave closer to the bellhousing, didn't adjust any rods/etc), with no avail.

I hope it's not the clutch... I can't afford another one right now.

I didn't install anything, I had a 4x4/diesel shop do it all. I'll ask about the disc though.
 

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Any possible chance that you could have installed the clutch disk backwards? Do you remember if it was marked "flywheel side" anywhere on the disk?
I've seen that one done before:eek: ! really sucks having to remedy it on a 4x4 with the T-case already in
 

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i had the same problem!

:confused: i have the dodge nv4500hd with the out put changed to a chevy . when i first installed the motor and tranny, it worked fine for a month then one day on the freeway it wont go in to fith gear . so i got off of the freeway and it was hard to go in every gear. so i replaced the slave.didnt help.check the fluid and it was gray . my transfercase fluid (gear oil ) got into my tranny and killed my scrincos. so i replaced them and my clutch , put new fluid in my 205. and it was better but not perfect. so i took the rod off of the slave and add 1/4 in to it and that help to .the more i drive it the better it is getting.i think cause the clutch is getting broke in or something!
 

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Don't know if it is correct, but I run the VN4500 fluid in both the tranny and the 205 I have.

Lost the seal in the 205 and they mixed, so after that I just ran the one oil in both. I've heard of others doing it and so far my 205 is fine.
 

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Easy Fix for Cross Contamination

When marrying a NP-205 to a NV-4500, a problem of lubricant cross contamination exists. This is because the drive coupling ( 23 spline or 29 spline) will not fit (seal) in the original NV-4500 output seal on the 4x4 version. Most people opt to 'trust' the seal in the NP-205 to retain the gear lube in the NP-205, and also not allow the special synthetic oil in the NV-4500 enter the NP-205. I dont trust the NP-205 as my only seal to prevent cross contamination, my NV-4500 is to expensive to screw up with gear oil.

Chicago Rawhide (NOW SKF) makes a seal # 19211 with specs as follows;
Shaft 1.938"
OD 2.567" (which is the same OD as original seal)
Width .313 (which is same width as the original seal)

This seal is plug and play as far as OD for fitting in the NV-4500. I take my drive coupling and turn it 1/2 ways in length to 1.938" with a mirror smooth seal finish.
From memory, (My notes are in the shop), I dont remember the exact diameter of the drive coupling, but your only taking a small cut, nothing that will weaken it at all.

Now I have a total seal on the NV-4500 side and the original NP-205 seal on the T Case. I go one step further, I clean the splines on the NP-205 and NV-4500 with solvent and then apply RTV Silicon to the spines. Now when the drive coupling is pushed on the splines the RTV Cures and will not allow any cross contamination to seep down the drive coupling splines should a seal on either side fail.

The Chicago Rawhide (SKF) seal is cheap, turning the drive coupling 1/2 ways to 1.938" would not cost that much if you had to have a machine shop do it for you.
Now you have total protection from lubricant cross contamination.

I do this little mod on all my trucks, cheap insurance.

Paul
 

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Good info Paul--I'm gonna do that on my future NV4500 to NP205 TC installs!
Thanks again for the info.
Bob B.---:beer:
 

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"Master-line-slave is the stock TJ unit. It's all one piece and sealed so there's definately no air in it. It was simply moved out of the way during the swap and then reinstalled. Bolts right up. Using the dodge adapter plate, dodge flywheel, dodge clutch. Dodge throwout lever."

I'm wondering if these parts have the correct bore diameter and travel length of component parts to insure that the clutch disengages properly. Were these parts compared to stock Dodge/Cummins parts to be sure they are capable of fully releasing the clutch? I understand you didn't do the work yourself so maybe it's something you need to bring up with the mechanics that did the work?

Has anyone else used this same combo without problems? That is, is this parts combo known for a fact to be a good match up?

On mine I used a non-standard clutch master/slave. I used the original '67 Dodge clutch slave and drilled/tapped the side of my NV4500 to mount it, and used the original '67 Dodge clutch master to power it. In order for that to work with the Dodge/Cummins clutch I had to properly set the depth of slave so it contacted release arm and had a full stroke to release. Seems now I need a wee bit more length on slave pushrod to get full release. Come to think of it, I only notice probelms after the truck is good and warmed up!
 

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In my 91 Dodge I run Castrol Syntorq in my 205 transfer case along with the NV4500 transmission. I looked at doing Paul's method of turning down the coupling sleeve but decided not to go that route. I prefer to have the splines run in oil as they were originally designed to do. My reasoning for this was I have another Dodge Cummins truck that has the Getrag G360 5 speed with the 205 transfer case. The previous owner rebuilt the transmission because the coupler between the 360 and the 205 failed at around 180,000 miles even though it was running in oil. Either method works.
 
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