t56 strength

[Randall488]

What's the t56 rated for? I'm askin bout the truck t56 not the car. I'm buyin a 1st gen cummins and the rag in it is shot. I'm not gonna race this truck or anyrhing but it will be my dd and I'm lookin for mileage and a fun drive to work and back.

 

[viperhauler]

i wanna say 650 hp, but i'm not sure why i think that...

 

[Randall488]

I thougjt there may of been a thread on here before but I couldn't find it.

 

[caveman]

The T56 is going to hold up fine the power of the Gen 1 Cummins, assuming it is a 2x4 and you are not going to tow heavy loads with it.

 

[Randall488]

Yes its in a d350 (2wd dually) the mst I could ever see myself hauling would be my V10 but even between that and the trailer that wouldn't crack 10k.. or would that be too much?

 

[caveman]

Yes its in a d350 (2wd dually) the mst I could ever see myself hauling would be my V10 but even between that and the trailer that wouldn't crack 10k.. or would that be too much?

You need to use a heavier duty trans because you are going to regularly tow with it. A used NV4500 is probably cheaper than a T56 anyway.

 

[viperhauler]

You need to use a heavier duty trans because you are going to regularly tow with it. A used NV4500 is probably cheaper than a T56 anyway.

i tend to agree with this... while i towed all the time, it was no more than 6k lbs... maybe 8 once or twice...

 

[Randall488]

Alright, my only problem with keeping a 5 speed is the.large gaps between gear ratios. I looked at the nv5600 but they're just as expensive as the tremec and harder to find parts for. Might just regear to 4:10's

 

[viperhauler]

what gear's in it now?

 

[mjd91]

The nv45 does have bigger gaps but I've seen them tow much more than 10k.
And yeah the nv56's are expensive. They are quite sought after.

 

[Randall488]

ive personally used the getrag in this truck to pull well over 20k in scrap iron, but its to the point where first and second are almost lost. you have to hold it in first no matter what or it will throw itself out of gear. the 5600 is stout yes but for the price and weight of the actuall gear box its a pain to install into a 1st gen, and right now its got the standard 3:54 gears in it. a 4500 would be nice but if im gonna pay for a 4500 and possibly have to rebuild it i'd rather rebuild the rag and find a used ring and pinion.

 

[viperhauler]

why isn't rebuilding yours the best option?

 

[Randall488]

The getrag is known for bein a very finiky. And id rather just have something that didn't need baby'd. The previous ownet had the trans lock up on himm before and caused him to jack knife on the highway.

 

[caveman]

id rather just have something that didn't need baby'd.

Based on the fact that you pulled 20k plus several times with it, I would say after a good rebuild, there is no reason you would need to baby it. It's served you well in the past and could do so again.

 

[Randall488]

The only reason its used like that is because its a work truck and the boss has the cash to replace it if it goes, as a private owner I don't have that luxury. Now if I was payed to rebuild it, then I purchased it after said rebuild, id be fine with that and wouldn't be concerend about a trans swap at all.

 

[STING]

I've seen and driven our stock T56s with 800+hp, definitely not rated for that, but I think these trannies slowly fail. I had mine rebuilt by Tick Performance to handle 700wrhp.

 

[SrtBrad]

held up with over 1000k hp for a long time

 

[chargerman426]

Tremec says the Viper spec T-56 is rated for 550 Ib-tq

 

[caveman]

It's not the power that the T56 is unhappy with, it's the weight of the load behind the truck.