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Tremec TR-4050 Install

folkenheath

Volcano Manifolds
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I am gathering parts for a customer build, he wants a 5 speed manual.

The options were to obtain a rebuilt NV4500 or get a new TR-4050, customer chose a new TR-4050 because by the time you find and rebuild a NV4500 the cost is pretty close.

I have already purchased a new Tremec TR-4050 (already in possession) through my distributor and ordered a new input gear for an NP205 from NFW. This allows a direct link to the TR4050 without any splined coupler.

I found a round large bearing NP205 I will rebuild for it. Customer wants the 205 simplicity, not the lower gearing of a 208 or 241. I may need a clocking ring, I will find out.

I will start a build thread for the whole project. Will be a 1973 K5 with a 502 BBC, EFI, TR4050, NP205, and 3/4 ton axles.

I am going to document just the TR4050 install here.

I am currently gathering clutch parts. Going with Centerforce on the clutch assembly, 12" if I can fit it, 11" if I can't, because BBC torque.

For the bellhousing. Tremec states the mounting matches the NV4500.

The only bellhousings I can find are Advance Adaptors 712576 or the Quicktime RM-8024.

However, the RM-8024 is made for the smaller transmission bore (5.125"), not the later one (5.600").

So I would have to bore it out. Not sure it is worth it vs the AA model unless it allows needed clutch clearance.

Unless there is a source for a GM 96 and newer NV4500 bellhousing? I'm assuming that's used only?

Another thing is both bell companies say it will only fit a 11" clutch, not a 12", and yet Centerforce says it's the same bolt pattern and will probably fit, especially with the Quicktime unit because its steel and not as thick as the cast aluminum. The depth clearance has to be the only limiter since the pressure plate isn't any wider on the bolt pattern.

My plan is to use a factory internal slave cylinder and not use a fork at all.

Any experience on the bellhousing and clutch clearance before I move forward and make it work?

I read somewhere the mounting bolt pattern changed on the newer NV4500 too, that true? If so maybe the Quicktime bell is not even an option.
 
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Odd coincidence, I saw a post on FB today about a guy in Louisiana building a K30 with a 496, TR4050, underdrive box, 205, etc. I know nothing about the trans, just thought it was crazy to see 2 posts about the same unusual trans in 1 day.
 
Odd coincidence, I saw a post on FB today about a guy in Louisiana building a K30 with a 496, TR4050, underdrive box, 205, etc. I know nothing about the trans, just thought it was crazy to see 2 posts about the same unusual trans in 1 day.
Here is what Tremec says about the TR-4050 in their catalog...

I can get this transmission through my distributor for anyone interested.

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I’m running the centerforce DF097310 with the oem bellhousing.
Thank you, I'll order the 12" DF clutch package Centerforce recommended for the Gen VI BBC.

I'll make a parts list when I am done gathering parts then show pictures of the install later. This is a big project so the final result will take a while, gathering parts now.

Since I already have the 502 short block, and the TR4050, I will likely mock that up once I have the bellhousing, flywheel, clutch, etc.

I will also mockup the NP205 once I have the input shaft from NFW. They also make an adaptor for Fig 8 style NP205s, the input shaft needs the large bearing housing.
 
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Has anyone driven a 4050? Curious how it was.

Are there upgrade parts available for it? Can you swap to 32spline output to work easily with the chevy tcases?
 
Has anyone driven a 4050? Curious how it was.

Are there upgrade parts available for it? Can you swap to 32spline output to work easily with the chevy tcases?
From reviews I've seen it's just like the 4500 but more refined and smoother shifting.

Heath, I'm looking forward to this build!
EFI too?
 
They are pretty slick units and tough. Silver sport transmission has done many of these on squares and sells a complete kit with everything needed for a squarebody.
 
Has anyone driven a 4050? Curious how it was.

Are there upgrade parts available for it? Can you swap to 32spline output to work easily with the chevy tcases?
I haven't driven one personally yet, supposed to be more refined according to Tremec.

The downside is thus far they only sell it with the Dodge style 23 spline output shaft. I do not believe you can swap output shafts, but I do not know. Perhaps in the future that will be an option.

From reviews I've seen it's just like the 4500 but more refined and smoother shifting.

Heath, I'm looking forward to this build!
EFI too?

Yes, most likely Edelbrock PF4 for this one since it will be an NA 502 and a manual trans.

They are pretty slick units and tough. Silver sport transmission has done many of these on squares and sells a complete kit with everything needed for a squarebody.

All the current aftermarket kits I am aware of for NP205, except the NFW, use only the weakest 10 spline GM input with a coupler. Then the 10 spline NP205 input becomes the weak link, I do not like that. I don't mind the 10 spline trans input, but the 10 spline input on the Tcase after the 6:1 1st gear is a recipe for carnage.

NFW makes the 23 spline female input for the NP205, no coupler needed, which makes it as strong as the transmission, which has a higher factory torque rating than the NV4500. Also, any coupler adds length, no coupler means you can bolt it directly up or use a thin 1/2" or so adaptor plate.

I suppose if you were using an NP241 you may be able to swap the input shaft for a 23 spline Dodge, but I am not sure if that will even interchange?

The TR4050 has a "std 6 bolt pattern" cast right into the back of the unit if you order the correct 4WD model. However, it is yet to be determined how that is clocked, I believe it is clocked like the Ford NP205 from what I have heard, I will confirm that once I get into it. That is why I might need a clocking ring or adaptor ring. NFW does have a Figure 8 style NP205 adaptor ring to bolt that model to the back of the TR4050.

I know you're going a different route, but yes they did change.

Thank you for the info, I believe the TR4050 matches the new style and includes provisions for an optional internal slave cylinder instead of a fork style, I'll confirm that.
 
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I know they're big and harder to find but why not consider a ZF6 6 speed manual trans?
Because they are big and harder to find. :D;)


On a more serious note I think that would be more ideal for a turbo diesel tow rig build but I think the TR4050 fits the application better for a mild BBC K5.

If the trans/tcase gets too long it could create rear driveshaft issues.
 
I’m running a 11” centerforce clutch with a stock ‘96 and later 4500 bell with my 4500 behind my 8.1. Plenty of holding power even though it’s an 11” unit.

I think you are going the right way with the internal slave oem bell. Unless something changed the AA bell uses the stock square body external slave parts. Which by itself isn’t bad, but I’ve run into some inconsistent clutch adjustment issues that I’m certain was an error in machining on the bell itself that fought us tooth and nail. The internal slave version lacks the adjustment but just works. The oem slave parts work well and feels like it should.
 
Because they are big and harder to find. :D;)


On a more serious note I think that would be more ideal for a turbo diesel tow rig build but I think the TR4050 fits the application better for a mild BBC K5.

If the trans/tcase gets too long it could create rear driveshaft issues.
Zf-6’s are massive, tall and long. Having driven a couple factory equipped Silverados with that trans, I don’t think they shift nearly as nice as a 4500 at least until you got a decent load behind it and then it shifts smooth like butter. But unloaded they are notchy.

I could totally see rear shaft length issues in a Blazer with the 6 speed. Not to mention a need for alterations to the floor pan to fit the thing in the truck.

I’m curious to see how the TREMEC works. I looked hard at them when they came out but couldn’t stomach the price.
 
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