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Discussion Starter #1
I have searched and read many threads on here. I have a 95 GM nv 4500 and was wondering about converting it to be compatible with a 6bt. I have searched and seen different post that says 96 plus gm nv will work and others say a 95 nv will work. I have checked the sticky and can’t seem to find a straight answer. If anyone can point me in the right direction it would be greatly appreciated! Thanks
 

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What ratio is first gear, and what is the diameter of the front bearing retainer. Most likely, you cannot convert your 95 to a Dodge-type configuration.
 

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Discussion Starter #4
I am still driving the truck so I cant measure the front bering retainer. I am not sure what the first gear ratio is. I guess I will try to find a number on it and make sure no PO changed the transmission out. Thanks for the help!
 

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Mine chevy was a 95. So I can help you out here.

Short answer... yes it'll work, with some work.

Long answer... to make it work you'll need a dodge input shaft and retainer, bellhousing and clutch setup. You'll have to get the dodge retainer machined out to fit the GM case and have the bolt holes slotted for the larger bolt circle on the GM case. The Dodge input shaft will swap right in though. Then when you put the bellhousing on you'll have to drill out the two lower holes. That's it. Not too terribly hard.

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Wow thanks that helps a bunch! This will really help me get going in the right direction. Was it difficult to get the machine work done at a local shop? What kind of cost was in on converting the 95 nv? Or is it any cheaper finding a 96+ gnv? Thanks again for the help!
 

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Mine chevy was a 95. So I can help you out here.

Short answer... yes it'll work, with some work.

Long answer... to make it work you'll need a dodge input shaft and retainer, bellhousing and clutch setup. You'll have to get the dodge retainer machined out to fit the GM case and have the bolt holes slotted for the larger bolt circle on the GM case. The Dodge input shaft will swap right in though. Then when you put the bellhousing on you'll have to drill out the two lower holes. That's it. Not too terribly hard.

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That assumes he has a 5.61 ratio NV4500. The 6.34 ratio 4500's ARE NOT convertible, period.
 

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So what's wrong with using a Chevy adapter? Then you can run any transmission, and when ( not if ) the NV shits the bed, your not looking for a Dodge dealer and a machine shop etc.
 

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That assumes he has a 5.61 ratio NV4500. The 6.34 ratio 4500's ARE NOT convertible, period.
My '95 had the 5.61 ratio. But it had the old style case with the smaller hole for the input shaft. And actually they are convertible. You have to swap out a gear (4th I believe?) So the input shaft will work, then still do everything else I mentioned. But they can be made to work. A fella on here has done several.




So what's wrong with using a Chevy adapter? Then you can run any transmission, and when ( not if ) the NV shits the bed, your not looking for a Dodge dealer and a machine shop etc.
This guy has an nv4500 and wants to use it. If he uses dodge parts then he has access to the huge aftermarket of dodge clutches and cheap replacement parts.

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Wow thanks that helps a bunch! This will really help me get going in the right direction. Was it difficult to get the machine work done at a local shop? What kind of cost was in on converting the 95 nv? Or is it any cheaper finding a 96+ gnv? Thanks again for the help!
I'm lucky, I've got an ag machine shop like 2 miles up the gravel road from my house. He charged me $75 to turn down the radius on the retainer and to slot the bolt holes. I drilled the two lower bellhousing bolt holes myself. So it cost me $75. I already had the dodge input and retainer from my donor truck. But you can find them for cheap on cummins forums from guys who upgrade their input shafts. They're always dumping the stock pieces for cheap.


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Huge aftermarket of Dodge clutches?
GM used the same bolt pattern on the pressure plate since the '50s, same input shat dimensions forever, he's driving a Chevy and will probably buy a Chevy parts truck. Outside of the "cheap ragged out bread truck motor" world, every clutch manufacturer world wide has been building clutches to Chevy dimensions for the last 60 years, I would guess there are 1,000 for every Dodge v-10 or 5.9 clutch.
 

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Past experiences that have been noted by our members has been the Chevy clutch set up is generally the most pricey due to the fact that it is the least common of the common used flywheel set ups. Yes you can get it to work in most cases but when you add up the initial costs it has been generally cheaper to use the factory Dodge Cummins set up.

According to my local Fritolay mechanic one of the main reasons that the stepvan fleets went to the automatic transmissions was clutch disk failures. It didn't take much for a driver to destroy the clutch disk. The failure generally occurred when the clutch disk decided to spit out one of the springs. The Chevy version used the same set up as the 6.2L GM diesel that the Cummins replaced. Being an 11-15/16 inch disk and pressure plate it had a reasonable amount of clamping power when using a stock 105 HP/265 FT-LB engine. 89-93 Dodge 6BT's used a 13 inch set up. 94-02[?] used a 12-1/2 inch set up. Both Dodge set ups were designed for use behind a high torque - low RPM Cummins diesel engine.

In general, you can buy a 4BT GM set up on average in the $700 range. Then add another $1250-1500 for an aftermarket clutch or you can buy a new Dodge 6BT flywheel, clutch assembly, release bearing and a Dodge Cummins set up at NAPA and have about half that amount in the conversion.

The "which NV4500" transmission issue seems so far to boil down to either in what part of model year run was your truck built or if the transmission ever been replaced. Both gear ratio sets have been reported for 95. The only real way you can find out is by checking the paper stick on tag on the shift tower area. The main issue reported when using this set up behind a Cummins 4BT has been the location of the clutch slave cylinder and the interference that it causes with the starter and the exhaust down pipe.
 

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The little springs in the disk get destroyed by harmonics. Might better leave the clutch a little soft than chase problems all the way to the asphalt.
Could be just a rumor, but I heard Conrail once replaced an EMD with an old bread truck motor once, soon as they attempted to move the train, all the rail shot right out from under the cars and there she sat on the ties.
 

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Discussion Starter #14
Well I did not make it home this weeked to check out what transmission I have. Is there any way to tell off the VIN number? I have the vin number but I understand it could have a different trans.

Thanks for all the information!!! Hopefully next weekend will be spent at home and not in a motel again!
 

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Huge aftermarket of Dodge clutches?
GM used the same bolt pattern on the pressure plate since the '50s, same input shat dimensions forever, he's driving a Chevy and will probably buy a Chevy parts truck. Outside of the "cheap ragged out bread truck motor" world, every clutch manufacturer world wide has been building clutches to Chevy dimensions for the last 60 years, I would guess there are 1,000 for every Dodge v-10 or 5.9 clutch.
I think BobS pretty much covered this, but if you use all the dodge parts you'll be buying a clutch made for a diesel, not a gas motor, plus dodge used a larger diameter input shaft that is quite a bit more stout than the GM one.

As a diesel parts dealer, I feel pretty safe in saying that there are dozens of quality clutch options for a cummins that will hold very large amounts of power. All of which are pretty reasonably priced. To find a similar clutch with a GM setup would be much more expensive.

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As a parts salesman you'll make a quick Buck selling input shafts that aren't needed. Looking at an NV as a whole, you realize the input shaft is Not the problem. From the failures I've seen, using any gear except 4th is the problem.
 

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I'm no NV4500 apologist, but the only times I have seen non-lube and non-5th gear related failures in the NV4500 is when someone puts far more torque through the trans than it was designed for. This is not a flaw in the trans but rather a lack of brains in the owner. Sounds like you have been hanging out on Comp D too much
 

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Discussion Starter #18
Well I finialy made it home to look and see what the transmission is the number on the side of the case is c-16812. It also had a number just above that one that was 5230. I am going to buy a mirror to look on top to see if there is any other numbers. Thanks again for all the information!
 

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Discussion Starter #19
I looked with a mirror and can find anymore numbers. I did look at the door tag and it shows a manufacture date of 9/95 if that helps any. Thanks!
 
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