Can a 4L80E handle a Duramax?

[DieselS10]

I currently have a 6.5/4L80 in my 4wd S10 and I am looking to upgrade to a Duramax since the 6.5 is a slug. There is absolutely no way that an Allison will fit in my truck, so I was wondering if the 4L80 can be built to handle a Duramax and if so what would I need to do with it.

At the most I only plan on adding a programmer to the D-max, my truck weighs 5750lbs, has 4.10 gears, 38" tires, and won't ever see trailer loads over 10,000lbs. Thanks in advance, Billy.

 

[lotsofmiles]

the dmax van has the 4l85e in it stock. an 'upgraded' 4l80.

dont know what you are planning for hp, but the van is very detuned. 250hp/460tq from the factory. big reason for detuning is the trans.

 

[ZR1160]

A built 4L80E would handle a Dmax with just a tune, but I believe the consensus is, anything more than that and boom!

 

[Mike L.]

4th gear is where you will sneeze the 4L85E. The sprag cannot hold it.

 

[JoshH]

Mike, are there no companies that make beefed up parts for the 4L80/85E that will fix the weak sprag?

 

[TrentNell]

Mike, are there no companies that make beefed up parts for the 4L80/85E that will fix the weak sprag?

sprag fix would require a stronger converter , dont know if anyone has a fix ?

 

[JoshH]

Aren't there a ton of companies that make converters for that trans?

 

[Mike L.]

sprag fix would require a stronger converter , dont know if anyone has a fix ?

Trent I am talking about the 4th gear sprag. We have no converter problems. When I built Diesel 5's Grand National I had PI build an Allison converter for that application. David brought me the engine and I did the measurements.

Josh
I have talked to a bunch of people about a beefier sprag and drum, but so far no one has stepped up. maybe some day.

 

[JoshH]

At what power levels do you think it will be an issue? What if it is in a 4000 lb or less truck?

 

[TrentNell]

Aren't there a ton of companies that make converters for that trans?

not shure but the sprag is used for lock up of the converter dont know how much space is availible for a stronger part . if i am wrong on the info sorry i am not a expert on the subject .

edit sorry mike i just saw your post on the drum sprag ..... i will zip it

 

[Mike L.]

At what power levels do you think it will be an issue? What if it is in a 4000 lb or less truck?

So far the Grand National is holding ( last I heard ) with a TTS extreme program and car weight at around 4500 lb. The car spins the tires at will which is a big plus because if you can keep the tires spinning there is less chance of damage in the trans. This care is being updated to a built motor and twin turbo's. Will the 4L85 hold? I'm betting against it. Who knows?

 

[JoshH]

It will be interesting to hear about how it holds up. I have a 2wd RC/SB 1/2 ton '82 Chevy pickup that I have dreams of swapping in a Duramax and making a drag truck. I think I can make it really light, and I would like to use a 4L85E for the transmission.

 

[lotsofmiles]

i talked to a place that said they can build the best 4l85 money can buy. when i asked if it would hold 500 hp they said all day long, when I asked about 1000tq his jaw hit the floor and he said 'are you serious? thats a lot of tq, are you sure? i dont know if it will hold that much tq. but if you give us $3500 and your trans we'll build it for you. but i cant tell you it will hold up to that kind of tq'.

hmmmmmm

 

[Mike L.]

i talked to a place that said they can build the best 4l85 money can buy. when i asked if it would hold 500 hp they said all day long, when I asked about 1000tq his jaw hit the floor and he said 'are you serious? thats a lot of tq, are you sure? i dont know if it will hold that much tq. but if you give us $3500 and your trans we'll build it for you. but i cant tell you it will hold up to that kind of tq'.

hmmmmmm

It won't.

 

[lotsofmiles]

kinda what I thought too.

 

[2500HeavyDuty]

that guy with the duramax mustang is running a 4L80E. it makes around 800hp

 

[ChampionTransmission]

Like Mike said 4th is going to be your weak spot. You can build a 4L80E to be pretty tough but there is only so much you can do.

 

[malibu795]

coan built a manual 4l85 for the NX dmax mustang..

called PATC said they got clutches(4th gear) for it.. but it would not hold up to drag raceing going into 4th.

everything else wouldnt be a problem...

basicly what mike said

 

[specialagentPK]

So I do not know the dimensions of it but isn't there a dodge tranny out there that is being used behind the duramax? If so why wouldn't that work as a subsitute?

 

[WolfLMM]

So I do not know the dimensions of it but isn't there a dodge tranny out there that is being used behind the duramax? If so why wouldn't that work as a subsitute?

X2 that's your best bet as of now.