Tremec TR-4050 Install

[folkenheath]

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.

I agree, I feel like the external hydraulic slave is kind of a halfway point that doesn't make much sense to me, you still got the fork, you still got the pivot ball, etc, but you also have hydraulics. If I am going hydraulic, I would rather eliminate the extra parts. If I have a fork, I think I would rather just use a mechanical link and eliminate the hydraulics, at that point you are just using the hydraulics for the ratio change, which can be done simpler mechanically. With the internal slave, you are eliminating more moving parts with the hydraulics and it ends up simpler.

Also, I previously called Centerforce and the dual friction 11" clutch was rated at about 620 lb-ft. The 12" model they recommended for this application was rated at about 750 lb-ft. The last mild BBC 502 I built and dyno'd for a truck was 555 HP and 607 lb-ft NA. This one will probably be more like 540 HP/ 590 lb-ft because I am using a different, even milder cam with the manual trans, that will peak at a lower RPM.

I'd rather have the load capacity buffer of the 12" clutch.

 

[folkenheath]

What I don't know is the piston diameters/area. Will the clutch pedal travel work with the factory square body clutch master cylinder and the internal slave from a 97 NV4500?

I could compare the pedal ratios and piston size of the two trucks, and see the difference, but I don't have that info yet.

Anyone done that?

 

[Chickntrk]

I drove a Jeep with a TR4050 in it at a show where silver sport had a booth set up. It is my understanding that it is the current manual transmission offering in overseas markets (where they still get cool options like that). It feels almost identical to a 4500 to me but I'm used to 465s and NP435s so even a 4500 is refined. I looked at swapping one into my Dodge but price tag stopped me.

Could you just use a Dodge NP205? Already 23 spline, round six bolt, and pass drop.

 

[folkenheath]

Could you just use a Dodge NP205? Already 23 spline, round six bolt, and pass drop.

I think you could yes, and I looked for one, but it was easier to find the Chevy 205 at least for me. Also, I think the Dodge 205 uses a male input gear and a coupler. The NFW female input eliminates the coupler and shortens the assembly.

Also, I think the Ford pattern is clocked different than a GM or Dodge? I still need to verify which one the trans actually has, I was told a Ford NP205 will bolt up with no adaptor, I haven't verified this. I have a Ford NP205 here for another project, so I can check when the time comes.

AA says the Jeep NP transfer cases will directly bolt up, so that may be a good solution for some people.

I don't have any Jeep transfer cases to compare to the Chevy pattern or the Ford pattern. I know one hole is clocked different, I read Ford is different, but then some people say the Ford bolts right up and some people say the Jeep bolts right up, so I have conflicting information and need to try it myself.

 

[Truckman4life]

I believe I read a ZF6 is like 4" longer than a 4L80E. I do agree that a 4500 shifts way nicer than the ZF. My 7.3L super duty service truck at work has one and I put a short throw shifter on it but they are still kinda dumb how the gears are. I dont think you could rip through the gears for fun either, at least not behind a diesel in an 18k lb service truck lol.

 

[folkenheath]

I opened the box on the pallet to confirm, it does match a 96 and newer GM NV4500 on the pilot bore and bolt pattern for the bellhousing.

The rear 6 bolt pattern does not have the top bolt on the center like GM does it, it appears to match a Ford clocking from initial inspection. However, I don't know if a Dodge matches a Ford or a GM 6 bolt pattern, or neither? I think the bolt circle is the same for all 3, it's just which is the odd bolt and where is the clocking.

I was able to pick it up by hand and put it back on the cardboard blocks to measure the front lower bolt spread, so its not terribly heavy, but not light either.

 

[muddybuddy]

She purdy

 

[sweetk30]

2001-2002 C3500HD with the NV4500/8.1L use a bigger 1.25” input vs 1.125”.

just showing clutch size is all in stock bell housing .

 

[folkenheath]

It also has the 2 threaded holes I believe are for the internal slave cylinder on the pilot.

I did wonder if I could bolt a GM tailshaft housing on there and bolt up the NP205, but it appears the bolt pattern is different for the tailshaft housing.

GM NV4500 4WD tailshaft housing





Top of TR4050 tailshaft housing...it appears the middle left bolt hole is definitely different, not symmetrical.

 

[folkenheath]

So it appears from my research all Dodge NP205s are the figure 8 variety and the newer adaptors adapt it to the 6 bolt pattern. But these adaptors all use male shafts and female couplers and appear to be 3 - 4 inches thick, so I think that option is out the window as it would require the same adaptor as a figure 8 GM and the Dodge version adds significant length.

The shortest assembly will be either to drill and tap the stock NP205 housing for the new clocking and zero extra length, or just install a thin adaptor/clocking ring to bolt the GM unit to the TR4050 and add ~1/2" of length. The Figure 8 version you could use the thin Figure 8 adaptor no problem.

I may need something like this, but the opposite if I decide not to drill and tap the 205 case in the mill. I don't know if the material is even there to drill and tap the case, I still need to determine that. Also, I find Ford 205 to GM trans, but not the other way around, so it may need to be custom at which point drill the stock case could be quicker.

 

[JoshHefnerX]

What does Tremec market as being on the end of this - or are they pretty much 'roll your own'?

 

[tarussell]

What does Tremec market as being on the end of this - or are they pretty much 'roll your own'?

They seem to cater to the Jeep crowd fairly heavily - mostly Dana 20’s & 300’s but it’s based off of some OEM offerings that are available south of the border in central and South America too.

The torque rating is nice but is limited in GVWR numbers so compare accordingly - not slamming it at all because it’s a nice piece; just saying that power ratings vary depending on service duty and weight applications factors.

 

[folkenheath]

What does Tremec market as being on the end of this - or are they pretty much 'roll your own'?

They do rate it at 600 ft-lbs of torque, based on a 15K GVWR, which is somewhat high for a light truck, not high like the ZF6, but still plenty high. They also market it as being "Similar to the defunct NV4500, but with several updates and improvements". However, they output is a 23 spline ~1 1/4" shaft, like Dodge used behind the Cummins until 1989 when they switched to the larger 29 spline. And GM has the 32 spline, so although it is similar to the NV4500 and has a higher torque rating, I think the 23 spline output is a limiting factor. However, it could be a stronger material than the old one, who knows. I know NWF told me their female 205 input is stronger and won't be the limiter, which is what I was concerned about, a stock 10 spline 205 input they used to use behind the SM465 is not strong, I was not willing to use that.

Below is what they put in their catalog...they say it's good for light truck and SUV. If you call them and ask for more info they send you the catalog. If you ask for more info than that they refer you to their dealer network. Most dealers just want to sell kits, and most kits are for Dodge or Ford, and the GM kits all seem to use the 10 spline 205 input. So since their isn't much info available I figured I would post it up here. If people want to buy from me that's great, if not at least they have the info they need.

Everyone knows TREMEC is the place to go for high-performance passenger car manual transmissions, but did you know that we now also have a transmission for the 4-wheel-drive community? The aftermarket TR-4050™ 5-speed is based on the same transmission TREMEC builds for OEM production in Mexican, Central American and South American markets—where you can still buy a new manual-equipped pickup truck! Offering a fantastic blend of strength, refinement and above all, driver control, the TR-4050 is practical enough for everyday use and robust enough for off-road weekend adventures!

*Based on TR-4050 used in current OEM production

• Similar to the defunct NV4500, but with several updates and improvements

• Die-cast aluminum case saves weight while offering considerable rigidity

• All gears synchronized, including reverse

• Countershaft-mounted 5th gear synchronizer reduces NVH in overdrive

• Aggressive 6.16 “granny” 1st gear and economical 0.76 overdrive

• 6-bolt PTO mount for operating hydraulic accessories

• Ideal for several light truck and SUV swaps

• Appropriate for all regular truck duties(towing, off-roading, etc.)

 

[tarussell]

They do rate it at 600 ft-lbs of torque, based on a 15K GVWR, which is somewhat high for a light truck, not high like the ZF6, but still plenty high. They also market it as being "Similar to the defunct NV4500, but with several updates and improvements". However, they output is a 23 spline ~1 1/4" shaft, like Dodge used behind the Cummins until 1989 when they switched to the larger 29 spline. And GM has the 32 spline, so although it is similar to the NV4500 and has a higher torque rating, I think the 23 spline output is a limiting factor. However, it could be a stronger material than the old one, who knows. I know NWF told me their female 205 input is stronger and won't be the limiter, which is what I was concerned about, a stock 10 spline 205 input they used to use behind the SM465 is not strong, I was not willing to use that.

Below is what they put in their catalog...they say it's good for light truck and SUV. If you call them and ask for more info they send you the catalog. If you ask for more info than that they refer you to their dealer network. Most dealers just want to sell kits, and most kits are for Dodge or Ford, and the GM kits all seem to use the 10 spline 205 input. So since there isn't much info available I figured I would post it up here. If people want to buy from me that's great, if not at least they have the info they need.

15K is impressive!
This trans could really be supported in the aftermarket if they opened up the output shaft spline options of the common 27, 31, 32 etc. - maybe with feedback that will happen and this trans will be a great option across the board.

The gear ratios are very nice too !

 

[JoshHefnerX]

Sounds like it's a good trans, but they don't really have their ducks in a row to be able to sell them efficiently. Different output shaft or some adapters and would be a lot more 'turn key' or choices. Or even some recommendations on what will attach to it...

Or their vendors are just weak...

 

[sweetk30]

my 3500-hd c3500hd trucks run the nv4500 in a 15k truck and work well . but this sounds like a good replacement just needs bigger output for more bolt in easy use .

 

[folkenheath]

I agree if they had a 32 spline output and a GM tailhousing pattern it would be much easier for GM swaps.

 

[skunked]

Very interesting, thanks for sharing @folkenheath

 

[folkenheath]

I got the clutch kit late last week, GM bell is on the way.

I am looking at slave cylinders. Does anyone have any experience with the GM unit vs the Luk unit?

These are all listed for a 1997 GM 2500 w/manual trans.

Luk unit is less than half the cost of the GM. I was leaning toward the GM unit, want the best one.

GM unit appears to be from Mexico, don't know where Luk unit is made?

GM




Luk

 

[JoshHefnerX]

I can tell you, I just ran into some problems w/ my t56.

I'm not sure if it's the same slave as you're looking at but looks pretty similar. Had one in there from the PO that was a 'precision' branded one - that retained the hydraulic line w/ the use of a big C clip. That's complete shit.

I believe the Precision brand also does LUK.

That C clip will probably retain the line once. but the clip will fail at some point - and require replacement of the slave unit. I just went through that.

The clip was inside the bellhousing, so I couldn't get a good eye on what was doing in there and fought with it for a while. Eventually it gave up and released.

However after replacement of the master with a new line, it would continuously pop out under load. This is fairly common.

So I did some digging and found that the 'duralast' brand from autozone - the 'prefilled' one. Is actually AP - branded just like OE. I've only just gotten it back together and was going to bleed/test tonight but the few pumps I've done on it were good and still retained on the line that would not stay in.

Duralast parts

Needing to pull the transmission in my Camaro, slave cyl keeps spitting out the line. Did some reading and some old threads mentioned that the Duralast one is actually OEM. Go down there and sure enough it's Marked w/ the AP logo like my master cyl res. Believe this is used on some of the...

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