Has anyone here mated a 6.2 or 6.5 to a T-56?

[Assnolax]

Just wondering if it has been done. Seems like with its gearing

(2.66/1.78/1.30/1.00/.74/.50)

Running 26" diameter tires and a 3.55 rear end

It would be perfect for a diesel. Keeping at around 1800 rpms for freeway 75mph cruising and 1800-1900 for decent towing speed in 5th gear.

Any thoughts? Thank you very much. If this has been covered Im sorry I couldnt find it and would appreciate the link. Thanks again.

[DmaxMaverick]

Welcome to the Forums!

Even a puny N/A6.2 would shred that tranny. Remember, even though the "sports car" engines may be similar, and even higher, in the torque area, that torque occurs at 2 and 3 times the RPM. Horsepower won't hurt a tranny, but torque will kill it. A well built T56 has issues holding up to moderately modified Vettes and Vipers. Compare an NV5600 or ZF-6 to the size and weight of the T56 (all 6 speeds). Even they have their issues with mod'd Diesels.

26" tires??? What's up with that? The OEM's are small enough as it is. I do understand, though, with a 2.66 first gear, you'd need 26" tires and/or 4.56 gears to get a good load moving. Clutches don't grow on trees.

There's a reason Diesel engines and their trannies are 25-50% more massive than their gasser counterparts.

Don't get me wrong, here. I'm not flaming you. Just offering some experienced insight.

[Assnolax]

Just the sort of information I am after. That whole measure 40 times cut once.

What transmission is going in that A body el camino that is being worked up for fuel economy? Thats pretty much what I have cooking in my head.

I dont care so very much about fuel economy as I do about 75mph capability when traveling with a negligable load. (few hundred lbs in the bed)
and still being able to get up hills when towing something in the 5000lb region.

The T-56 just seemed like such an easy replacement for a T 10 or Muncie.

Will the ZF6 fit? Modifications to the tunnel arent a problem just dont want to be reaching behind me to shift.

Thank you very much. Do appreciate the input.

[DmaxMaverick]

I think you'd have serious issues fitting a ZF in a car chassis. You'll have to modify the tunnel....and the asphault. They're big....and heavy. Same goes for all the manual truck trannies. You'd be better off with a 4L80E auto, as the OD's are close to the same with all of them. If you aren't turbo'ing, a good 700R4 would work well, and be less parasitic than all the other autos, and it doesn't require a confuser or vacuum. A T56 would probably work OK in a car chassis, but I'd have it built first. The low end torque and "Diesel pulse" would probably shake it apart pretty quick stock. And....a 26" tire would be much better suited on a car chassis.

Give us some idea of exactly what you have in mind. You'll get lots of suggestions, and probably hear from some that have actually done it.

[Assnolax]

After a truck would prefer 60s Chevy for the styling. Have access to an El camino that I can get pretty cheap and I do love them so that would be great but the C10s and the variety are great too. Daily driver would just need to hold a couple hundred lbs of tools and equipment and have the ability to tow trailers up to 5000lbs. Usually in the 1-3 range though.
I would prefer a manual transmission and I love the diesel clatter. It would be my new work truck so reliability will come into play when considering.

When Im not towing Im usually going 75 mph if its open highway.
When towing 55-60 if on flat land and whatever it will do on the hills.
Right now have a 91 ranger and that thing does alright but I want something more fun.


Isnt the ZF-6 also used in corvettes? No problems with tunnel work, Im okay with a mig. I would just need to research what crashed vehicle to take the parts from.

Thank you very much, Im much obliged.

[DmaxMaverick]

The ZF-6 would be way overkill for a low power 1/2 ton. If you try to put it in an El Camino, you not only have to mod the tunnel, but the asphault as well. These things are HUGE. For light weight, you won't need a 6 speed. The need for close gears isn't there. The El Camino would probably be happier with an auto or smaller OD 5 speed.

A 6.2/6.5 powered vehicle would be a nice improvement over your '91 Ranger. Do it right, and you can expect highway mileage in the mid to high 20's easily.

[Assnolax]

Alright so the ZF6 is overkill. Is the diesel one any different than the corvette one?

NV4500 Seem like it would be alright?

1st....................................5.61:1
2nd...................................3.04:1
3rd....................................1.67:1
4th....................................1.00:1
5th.......................................75:1
Reverse.............................5.04:1

NV4500 in an el camino with 26" Diameter tires and 2.55 rear.
Would that be good in an el camino?

Would a C10 be a more appropriate choice being more of a truck?

I really do appreciate all of this feedback. Thank you very much.


As an added note, to be honest though, I do like the idea of overkill.

[DmaxMaverick]

I am also a big fan of overkill. But, there comes a time when it becomes ridiculous, and lacks practicallity. Even the NV4500 is a big'un. OK for a truck, but not the El Camino. Big also has another drawback. Parasitic loss. The bigger trannies take more power (economy) to turn them. A 700R4 tranny has as good an economy curve as an NV4500, due to size and loss. Also, clutches are a big headache for LT Diesels. For your needs, I think a light truck would be a better route. The El Camino would be fine for a commuter, but would lack as a truck. Definitely not overkill.

[Assnolax]

Alright I think I will take a few days to mull this all over then come back and pick the brains here again after some additional research.


Thank you very much.

I would prefer to avoid automatic transmissions so will be looking into what is available in the standards.

Have a good example of a light truck? The C/K series perhaps? Thanks

[ozbrad]

G'day Gents,

I'm a new member and this is my first post.

Lets not dismiss the T56 so quickly, I would love to know if its been done and how its going.

I think it might stand up to it.

The LS2 torque curve is pretty impressive (330lb/ft@1500rpm, 350@2000, 400@4500) and in Oz we use the LS2 and T56 in a 1700kg car - thats tows 1600kg that about 7,200lb total. (Thats where the GTO came from).

I've just bought a 6.2 and will turbo it and use it in a '42 dodge 3/4 ton truck.
I was thinking of using the t56 with an NP200 or 205 transfercase.

I think the T56 might be worth some discussion (on a 6.2 or 6.5, not a high torque duramax).

Any opinions??

Cheers.

[ozbrad]

http://www.edmunds.com/new/research/dodge/rampickup1500srt10.html

thats the clincher, it the box I'll use.

[Assnolax]

The viper box would have been what I was going to use as well.

ddperformance sells them ready to go to bolt up to old chevys. You get to still use a mechanical clutch and speedo.
http://www.ddperformance.com/GM%20T56.htm

Im in no hurry still researching. For all I know I might just buy a low miles retired almbulance for the heavy long haul stuff and an el camino for the lighter stuff and shorter jaunts between worksites.

Still undecided still researching, never been too well informed on diesels, taking care of that.

[john8662]

I would also consider the T56 manual still...

I had one in a '97 Z28 camaro LT1 once (yeah, hard to see me in a gasser eh).

Anyways, that tranny was tough, as were most of them in cars way more modded than mine.

Dmax is right, torque is the killer/twister of transmissions, especially manuals.

The first gen T56 was a good tranny, those put in cars (mainly camaros/firebirds F-body) up till '97, the later isn't rated for as much torque.

IIRC, the T56 is rated for 450 ft/lbs. torque, the later is for 400 ft/lbs.

A stock 6.5TD is putting out ~380 ft./lbs, so, you won't have too much of a safety margin, but it is doable. This is also considering a stock un-modded T56, yeah the clutch is going to be fun, I had to go down that road as well.

One bad of the T56, they're not cheap!!! Many are looking for them.

J

[dragonriot]

Sort of off the current subject, but how would you go about mounting up a transfer case to that T-56? No one has made an aftermarket adaptor to link up to an NP205 or NP241 for the T-56... if you plan on a 4x4 Diesel, stay away from the T-56..

[DmaxMaverick]

Sort of off the current subject, but how would you go about mounting up a transfer case to that T-56? No one has made an aftermarket adaptor to link up to an NP205 or NP241 for the T-56... if you plan on a 4x4 Diesel, stay away from the T-56..

#1 passtime in CA, even gearboxes are doing it.....Divorce it. Piece of cake.

[Robyn]

The 700 R4 if built with the right stuff will tolerate a 6.5 turbo and then some.
You need the heavy duty 3-4 clutch pack and the special HD 2-4 band as well as the corvette servo. The HD sprague and low roller clutch update.
13 vane pump.
Aftermarket reenforced input drum and the Beast sun shell.
A good shift kit and a diesel converter.
The 700 will tolerate quite a beating if its built right.
The nice part of the 700 is that it needs no computer to run it.
Go with an 88-90 K case V8 or diesel unit