Tremec TR-4050 swap

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WranglerTJForum

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I bit the bullet today and ordered a full Tremec TR-4050 swap conversion for my '73 K10.

The 700R4 that is in there now just doesn't pair nicely with that Blueprint Engines 396 SBC stroker. I grew up driving manuals and I think this truck is going to be an absolute blast to drive with the TR-4050.

Will keep you guys posted but this is my project for the winter.
 

gilby959798

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I plan to order one at the beginning of the year (hopefully) if I get the body work where I want it, along with a 383. What T case do you have currently?
 

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The following is just a heads up, not trying to rain on anyone’s parade:

Is that trans supposed to feel like an NV4500? The shifting of an nv4500 is long and not very sporty. I have an nv4500 that I installed that I will likely be taking out to reinstall an automatic, because the truck is slower with the manual.

I didn’t think I’d care, but I do. The 4500 is a truck transmission built to be tough, but not racing through the gears. Once you are in a gear it’s okay, but you won’t be pulling any holeshots.

If I had it to do all over again, I would have went with a 4l80e right out of the gate. Also, if your tremec uses a hydraulic clutch, the factory hydro pedals are not easy to find and often pricey.
 

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I plan to order one at the beginning of the year (hopefully) if I get the body work where I want it, along with a 383. What T case do you have currently?

I've got the NP205.

The following is just a heads up, not trying to rain on anyone’s parade:

Is that trans supposed to feel like an NV4500? The shifting of an nv4500 is long and not very sporty. I have an nv4500 that I installed that I will likely be taking out to reinstall an automatic, because the truck is slower with the manual.

I didn’t think I’d care, but I do. The 4500 is a truck transmission built to be tough, but not racing through the gears. Once you are in a gear it’s okay, but you won’t be pulling any holeshots.

If I had it to do all over again, I would have went with a 4l80e right out of the gate. Also, if your tremec uses a hydraulic clutch, the factory hydro pedals are not easy to find and often pricey.

No, this transmission is a huge improvement over the NV4500. It shifts like a sporty transmission, not like a truck transmission. That's why I went this route. The TR-4050 is also supposed to be tougher than the NV4500 and much easier to get parts for.

Very cool! I put a T56 in mine 2 years ago and next to the LS, it's the best thing I ever did to my truck

T56 is a nice transmission, I've owned one before! I love driving manuals, it never gets old (unless you're in traffic).
 

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I've got the NP205.



No, this transmission is a huge improvement over the NV4500. It shifts like a sporty transmission, not like a truck transmission. That's why I went this route. The TR-4050 is also supposed to be tougher than the NV4500 and much easier to get parts for.



T56 is a nice transmission, I've owned one before! I love driving manuals, it never gets old (unless you're in traffic).
How many spline is your 205 and the tr4050 output?
 

bucket

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I thought they still didn't offer a 4050 with a common GM splined output?
 

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The quote i got said it had an adapter to a 10 spline t case input shaft
 

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The quote i got said it had an adapter to a 10 spline t case input shaft

Here's the problem with what they are trying to sell to the GM truck owner. The 10 spline coupler was the big weak point with the old 465/205 combo... many people don't care for it. It also limits t-case selection to 40-50 year old 205's and that's just about it. People that pony up for a modern overdrive trans are probably going to prefer a quieter, smoother, lighter t-case that also has a better low range. So here they are, selling a nice modern trans with the super common round pattern t-case flange, but to run it you need to use an ancient t-case, an undesirable 10-spline coupler, a t-case spacer AND a round pattern to figure 8 pattern adapter as well.

If they would just offer them with a 32 spline output, a buyer could then have their pick of a 205, a 208, or 241, etc. Without a bunch of adapters too. Even if it was just a 32 spine adapter on the 29 spline (or whatever it comes with) output and a guy had to run a spacer, it would still be a FAR better option than the 10 spline arrangement.

You must be registered for see images attach

^stolen from American Powertrain's site^
 
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Oh and also since they basically limit you to a 205 and there is no shifter mounting provision anywhere in that setup, a buyer would also have to buy cable shifters or fabricate their own shifter bracket.
 

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I've got the NP205.



No, this transmission is a huge improvement over the NV4500. It shifts like a sporty transmission, not like a truck transmission. That's why I went this route. The TR-4050 is also supposed to be tougher than the NV4500 and much easier to get parts for.



T56 is a nice transmission, I've owned one before! I love driving manuals, it never gets old (unless you're in traffic).

If you have a 700r4 but still have an np205, your t-case input will be 27 spline.

Have you driven a truck with the tr4050 trans already?
 

gilby959798

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Here's the problem with what they are trying to sell to the GM truck owner. The 10 spline coupler was the big weak point with the old 465/205 combo... many people don't care for it. It also limits t-case selection to 40-50 year old 205's and that's just about it. People that pony up for a modern overdrive trans are probably going to prefer a quieter, smoother, lighter t-case that also has a better low range. So here they are, selling a nice modern trans with the super common round pattern t-case flange, but to run it you need to use an ancient t-case, an undesirable 10-spline coupler, a t-case spacer AND a round pattern to figure 8 pattern adapter as well.

If they would just offer them with a 32 spline output, a buyer could then have their pick of a 205, a 208, or 241, etc. Without a bunch of adapters too. Even if it was just a 32 spine adapter on the 29 spline (or whatever it comes with) output and a guy had to run a spacer, it would still be a FAR better option than the 10 spline arrangement.

You must be registered for see images attach

^stolen from Tremec's site^
But I already have the ancient T case LOL. I know I will be bale to fab something up for the shifter.
 

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But I already have the ancient T case LOL. I know I will be bale to fab something up for the shifter.

Yeah, as do a lot of people. But what about all the people with 80's and later trucks that already have the round pattern cases? And all the guys doing LS swaps and want a completely modern drivetrain?

I just think that so far, they have missed their mark with the tr4050 market. They could potentially sell a substantial amount more if there was a common 32 spline output option.
 

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If you have a 700r4 but still have an np205, your t-case input will be 27 spline.

Have you driven a truck with the tr4050 trans already?

Yes, the swap kit comes with the 10-spline conversion. It wasn't cheap, but Silver Sport Transmissions set me up with everything I need for the conversion. Of course I say that and I'm sure that once I start tearing things apart I'll find something else that wasn't included. In any case, the 10-spline conversion is included.

I have not driven anything with a TR-4050 in it, but I've read overwhelmingly positive things. Namely that it takes everything about the NV4500 and improves on it in a multitude of ways. The guys who have done the swap really seem to be happy with it.
 

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Yes, the swap kit comes with the 10-spline conversion. It wasn't cheap, but Silver Sport Transmissions set me up with everything I need for the conversion. Of course I say that and I'm sure that once I start tearing things apart I'll find something else that wasn't included. In any case, the 10-spline conversion is included.

I have not driven anything with a TR-4050 in it, but I've read overwhelmingly positive things. Namely that it takes everything about the NV4500 and improves on it in a multitude of ways. The guys who have done the swap really seem to be happy with it.
Just what I've read on the transmission is making me consider it for my older C20's
 

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