Tremec TR-4050 swap

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WranglerTJForum

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Just what I've read on the transmission is making me consider it for my older C20's

The gear ratios are excellent too. 6.16 1st gear and 6.03 reverse.

From what everyone says it doesn't have any of the notchiness that is so common with the NV4500 (and the NV3500 for that matter) transmissions. Parts are much more available, it's rated for more power, etc.

I'm not sure how long this is going to take me to install on my back in my dirt floor shop, but I'll try to have it done sometime during the winter.

I was heavily leaning towards the NV4500 swap until I stumbled onto the TR-4050. It's like they took the NV4500 and improved all of the shortfalls with it (which I'm assuming is what they had in mind when they developed it).
 

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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.
Being that all I've messed with for old trucks has been 2wd (other than the K5 I never really did much on), I had not considered all of those points. It would be fairly simple for them to offer different output spine counts. You should call them and inform them of this lol
 

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I would think that 2wd ( C trucks ) v. 4wd ( K trucks ) would be 2 completely different cases? I'm all in with a T56 / ls1/2/3 etc. swap for 2wd - fast shifting for a street racer, however surely you are not worried about street racing or autocrossing your K truck?

4wd would be all about simplicity, reliability and / or rock crawling if you are into "competition" no? in which case the NP205 gear case "dinosaur" together with D60 axles and a grumpy old manual case would be just fine for getting you where you need to go in the backwoods.

If you are into rock crawling you would want an automatic ( no clutch slip ) and a doubler ( Atlas case anyone ? ) etc. etc. - or am I missing the point here??..

The Tremec replacement for an NV4500 is very interesting as they ( NV4500's ) are unicorn s*** over here, and stupid prices for a used box of unknown condition / origin, with no peripherals ( typically 5 - 6K, no bellhousing, adaptors, pedals etc. - often dodge models ). Would much rather have a new ( quality manufacture ) box, and be able to source all the peripherals from the OEM..

Lots of pics of how the conversion goes please, and also how it drives once installed ..
 
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Looking forward to this. I'm tired of my NV4500. Last time I checked I couldn't find the special fluid anywhere and the Mobil or Redline fluid ruins the shift quality....3rd synchro is out and it's almost time for a clutch. It'd be nice to just swap one of these in instead.
 

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You should call them and inform them of this lol

I looked into this when the 4500 on my dually was grinding bad. The "gm" version 1st gear is lower than the 4500 which is already useless unless I'm towing. The "ford" version has a higher first, which is still lower than a 4500 but not as bad as the "gm" version.

I called to ask about a "ford" gear ratios setup for a gm an they did not want to discuss any changes, just simply said it wasn't happening, that what they had was it an basically ended the conversation. I get its marketed to the 4wd guys an thats what they want. But it sucks as a 2wd version with those ratios imo.
 

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Looking forward to this. I'm tired of my NV4500. Last time I checked I couldn't find the special fluid anywhere and the Mobil or Redline fluid ruins the shift quality....3rd synchro is out and it's almost time for a clutch. It'd be nice to just swap one of these in instead.

Yep, I almost went the NV4500 route but the more I dug into it the more it seemed like a lot of people were happy. Special fluid, crunchy gears, harder to find parts for, etc.

Coming from the Jeep Wrangler world (TJs) I'm very familiar with the NV3500 for the TJs. It's notorious for the most problematic of the 5-speed manuals offered for the TJ platform. They're loud, they crunch when putting them in gear, and if you need a rebuild or replacement, good luck! Whenever they need replacing we always tell people to just swap it out in favor of an AX-15.

Anyways, I'm glad I stumbled upon the TR-4050. I'm looking forward to it quite a bit and I will certainly update this thread with my thoughts and opinions on the transmission once it's up-and-running.
 

gilby959798

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I am really looking forward to the progress since I am a few months behind you. When I got a quote for it, it was just under $5k. Do you mind saying what your quote was?
 

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I looked into this when the 4500 on my dually was grinding bad. The "gm" version 1st gear is lower than the 4500 which is already useless unless I'm towing. The "ford" version has a higher first, which is still lower than a 4500 but not as bad as the "gm" version.

I called to ask about a "ford" gear ratios setup for a gm an they did not want to discuss any changes, just simply said it wasn't happening, that what they had was it an basically ended the conversation. I get its marketed to the 4wd guys an thats what they want. But it sucks as a 2wd version with those ratios imo.
Well that's a bummer. I know these things will probably be fairly low sellers anyway but you're losing another bit of the market not catering to 2wd guys as well. Not like it's hard or even all that expensive (relatively) to come up with 1 more 1st gearset
 

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Well that's a bummer. I know these things will probably be fairly low sellers anyway but you're losing another bit of the market not catering to 2wd guys as well. Not like it's hard or even all that expensive (relatively) to come up with 1 more 1st gearset
Honestly with my 4.56s I would prefer a different 1st and 5th gear set. Give me something that I can actually use 1st and something that makes 5th like 2k RPMs with 33s.
 

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I would think that you could swap a 23 spline dodge NP205 input into a round case and get a direct bolt-up, assuming you have the round case, although you might need to sort out the input bearing as the 23 spline might be a small diameter shaft, and the round pattern GM cases are large bearing. That said, I agree that Tremec should be able to sell a lot more of these if they offer it with a 32 spline output...
 

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Honestly with my 4.56s I would prefer a different 1st and 5th gear set. Give me something that I can actually use 1st and something that makes 5th like 2k RPMs with 33s.
No affiliation with this site, but it has a really handy calculator/visualizer for transmission, gear ratio, and tire size comparisons. It even has 2 sets for the TR4050 already. With 33's and 4.56 on the close ratio setup, your 5th gear should be 2500 at 70, and depending on red line, shifting at ~20, ~40, and ~70 at heavy throttle

You can add a transfer case ratio as well to see what that does too, and add a different axle ratio or tire size to compare. Really pretty handy page.
 
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WranglerTJForum

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I am really looking forward to the progress since I am a few months behind you. When I got a quote for it, it was just under $5k. Do you mind saying what your quote was?
$6700

Not cheap but keep in mind that was for everything needed including all the way down to the shift boot. That also included freight.
 

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Honestly with my 4.56s I would prefer a different 1st and 5th gear set. Give me something that I can actually use 1st and something that makes 5th like 2k RPMs with 33s.
I actually made a mistake when I ordered my T56. I ordered the close ratio one, thinking it would be beneficial over the wide ratio for my particular setup and it's not, 1st gear is way too tall. So I'm actually going deeper on the rear gears (3.90 to either 4.30 or 4.56) and gonna change 6th to the taller one (.50 vs .67) since I have to replace my input shaft anyway
 

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