4L80E transmission conversion

[tractorface]

I have been researching all sorts of options for the Automatic in my Ram. Anyone know much about the 4L80E. The price to convert is in line with a full tilt and Boogie trans from any of the usual sources. Just curious what the consensus is.

Thanks



Exerpt from e-mail from Jet Transmissions



"We can supply you with the transmission and the electronic components to make it shift. The adapter plate for the motor is available from Cummins. Our transmission kit comes complete with transmission, converter, wiring harness, computer, custom software package and external oil cooler. The kit for diesel vehicles sells for $****. 00. We custom build all of our transmissions to order, so please allow 2-3 weeks lead time. "

 

[Chief USA]

I had a 4L80E trans. in my 1993 K2500 Suburban and it was not worth crap for towing. Mag-Hytech pan, syn. trans. fluid, aux. trans. cooler. It still over heated and puked oil when towing. Problem was with the torque convert and lock up criteria. The converter locks up ONLY in OD & D. Once you are on a hill and it shifts to 2nd gear, there goes the lock up and the trans. temp shoots off the chart. Piece of junk. That is the prime reason I traded my Suburban in on my Dodge Cummins 2500 4 x 4 HO. There is NO comparison with respect to towing ability. I love my NV5600 trans. Save your money.

 

[DWest]

4L80

I have to disagree on this one. My 95 6. 5 was running about 280 hp to the rear wheels and the 4L80 held up like a tank for 178,000 miles. It only required service every 30,000 miles unlike my Dodges 15,000. Shifted much smoother and never got hot, granted I never towed over 7,000 lbs with it. The Dodge trany is my one gripe in this truck that could have easily been remedied by DC to handle this motors potential. Remember that 10 more HP in the HO and you can't get the auto, need I say more. DW

 

[TnLRacing]

As per Trans-Go . . the 4L80E is a great trans and with a few simple mod can easily handle 900hp

 

[Todd G]

Maybe 900hp at 6000rpm. I'll bet 400hp at 1800rpm would kill it.

 

[HillCountrykid]

Almost every transmission I've seen is rated in ft/lbs.

 

[TnLRacing]

Tractorface... Im goning to do a little more research on this and see what I can come up with... ... This is the exact wording on the lit I have from Trans-Go:



" This is the trans that off-roaders, big horsepower streeter and racers have been wanting. Somethin with an overdrive gear that you can beat the snot out of without giving it or you a runny nose. It just gets comfortable at about 900hp and will handle a bunch more with a few special parts. "





Now the question is how much better is this trans than the 618, and will it be cost efective to try and convert a DC to a 4l80e. My guess is that by the time you buy all the needed conversion parts to make this doable. . you could have just spent the money on upgrading your current trans

 

[tractorface]

Your right

I really don't see any cost savings at all over a 47RE with all the bells and whistles. Just wondering if it could be a better way to go. I am inclined to go with one of the proven 47RE guys even if choosing which one has me crazy. I think I'm gona do it soon before I can't afford to do it and have a broken truck

 

[DWest]

conversion

I agree that it would be more practical to build your DC trany to handle your power. What I was getting at was how poor the Dodge transmission is set up in stock form. If you use it with stock power towing heavy loads on a daily basis it will not hold up nearly as well as the 4L80. Shame on DC for putting this setup in their trucks. DW

 

[curatchko]

The deal on the 4l80E is that it's a TH400 with overdrive... basically. Same internals as a TH400, and this comes from the GM Engineer at GM Truck. Killer trans... .



The 47re is a 727 with overdrive. There ain't NOTHING diesel about our transmissions... . same trans thats in the V10 etc...



Which is stronger a 727 or a TH400? That answer is easy.

 

[Ncostello]

I had a 94 Chevy 2500 8 lug 2wd prior to my Dodge Cummins. Its 4L80E was a very good transmission. All I had was a 350 gas but I pulled some very heavy loads (overloads?) and it never gave a hint of trouble. I've read elsewhere on the internet where its a very durable and can handle torque. A local transmission shop (one I trust cause I know the owner personally) said they are very good but do have their weaknesses. Some fairly simple mods, that require teardown, make it alot better he said. I've often wondered how it would do behind a Cummins.



FWIW... this is GM's "big" automatic. I think the 4L60E is also used in HD applications. Only thing I had to get was a speedo sensor for it once. The GM parts guy said... "Oh. . you got the beefy transmission in yours" when he was looking up the part.



Isn't that the transmission the 6. 5L Diesel Hummers get?

 

[csutton7]

DTT and I talked of this and then they looked into this with chris strickland while he was up there and it turned out to be too costly to do--- Cummins does make the adapters to do it, but you need the stand alone computer and I think this is where things went nuts--if I remember right things weren't so easily adapted and the computer was a whole nother issue----



a previous member Hadi put a cummins into his Hummer(4-5yrs ago) with the 4l80e, but it again wasn't cheap--this is the only one I know of being behind a cummins--his saving grace was that the Hummer came with GM drivetrain and this helped a lot----



and really now there is no reason to think of this as there are co's out there who have trannies to handle what 99% of us drive---chris

 

[catoiler]

Which is stronger a 727 or a TH400? That answer is easy.

Your right the 727 is much better than the 400. Know what is amazing?take alum. 904 guts in a 727 and see what you get!

 

[curatchko]

You get a proflight. I'm well aware of that transmission because I have one built by A1. I don't believe it could live behind our deal.



Th400 is the king of heavy duty transmissions in pass cars and light trucks... . 727 is a grenade with the pin pulled.

 

[catoiler]

Well,If i didn't get rid of my 96 we had on that we were going to try with 2. 70 gears and a nice converter to see what it would do!

It's nice to know the owner of Pro Trans and get to try new stuff!!

 

[fox]

There was a story a few years ago about a guy who wanted a Cummins in his ford. His mechanic asked about the trans and the customer insisted he use the t-400. When they got it going they used a fresh t-400 with a shift kit. The Cummins broke a shaft in it --TWICE. They ended up with the 618 with a kit and did not have any problems.

The T-400 is heavier in rotational weight but does not have a shift timing issue either.

FAR CHEAPER and EASIER to use the Dodge trans but it needs to be set up CORRECTLY.

If you want something special be ready to spend.

 

[Stefan Kondolay]

We have done the Cummins conversion and it is a lot cheaper if you already have a Chev drive train and all you want to do is add a Cummins motor to it.



Adapter kit is available from Cummins, Bill's advice is to dial 911 before you make the call to Cummins because the pricing may send you into Cardiac Arrest.



Here is a complete list of the Cummins part numbers if you want them for referencing the kit.



Quantity Part # Description

8 3901395 screw,hex head cap

1 3907701 adapter,crankshaft

1 3908124 transmission adapter

6 3910665 screw. jex flange head

1 3918957 flexplate

1 3923049 ring clamping

2 3910270 dowel pin

6 3913638 hex flange

1 3904181 plug threaded

1 3910248 plug o ring

1 3910260 seal ring

2 3912072 screw

12 3920447 screw

1 3925234 plate,cover



Now you have it , good luck.

 

[csutton7]

Stefan--thanks for jumping in and helping out with that info... ... ... and don't forget the transmission, computer for transmission and I'm sure there's a couple of other things that we are missing---dirveshaft issues maybe and ?????----chris