Im getting an l92 418ci with a D1 procharger at 14 Psi fitted in a 2008 Gmc Sierra single cabin 4x4 and should be putting out 700-750 rwhp approximately.

Decided to go with the 4l65e because of the ease of installation and those 3 companies provide them rated at 800 rwhp.

Performabuilt- Level 3 (The invincible)
RPM - Level 5
FLT - Level 5

Theyre all great and just wanted to ask if you had any experience with any of those transmissions and what you would recommend to go with and why?


Thanks for any input.

 

I'll be the first to say that I would not recommend a 4l6X in that vehicle with that amount of rwhp. An 80E is what you need to be thinking about. I have guys pushing those numbers in a vehicle like yours but I do not recommend it in a full weight truck. Just want to be honest here. If others tell you it will last I wish you the best of luck. Vince

 

I have to say I would agree with Vince at that power level and a 4x4 its gonna be hard on the trans. But I also can understand due to the difficulty and expense of the swap not wanting to go with the 80e , I would certainly go with the best each of us have to offer with the 60e in our case the level 3 and in There case I think its the level 5.
In any of our cases I would say you should realistically expect to at minimum have to have it refreshed/restored yearly and how long it last or when it fails will depend on your driving, That much power in a heavy truck with the 60e s alot to ask.
Please let me know if we can be of any help we do have some very good specials going right now.
Frank at PerformaBuilt

 

Performabuilt hands down u won't regret it!!

 

+1 for performabuilt

 

Check out performancetrucks.net the sister site of ls1tech.com. You will find that the majority of the fast and big HP trucks are running FLT transmissions and they are doing it for a reason.

 

I'm putting down about 500 to the wheels right now in my turbo'd extended cab and with my new motor ill be going to an 80E for sure... Ill be around the 750whp range myself.

I've ran this trans/converter for 2yrs with well over a hundred nitrous passes and close to 200 on motor, none yet on the turbo since its a new addition but I called Vince today and we are already planning an 80E to go behind the new bored 6L...

The truck weighs right around 4000lbs raceweight.

Do yourself a favor and go with an 80E to begin with and save money down the road and a lot of headache... Coming from someone who knows

 

I agree with Vince and Frank. I don't know a whole lot about transmissions, but what I do know is that kind of power in a full-weight truck is a lot to ask from a transmission meant to handle 300 ft-lbs of torque. The sponsors on this site do a great job with 4L60E's no doubt, but all the fancy drilling and expensive parts combos in the world won't change the fact the 4L60E is a medium duty transmission. The best built 4L60E in the world won't hold up forever in that kind of severe duty environment.

The 4L80E is made for heavy duty vehicles - 6,000 lb buses and such. The 4L80E may seem expensive at first due to the cost and increased difficulty of the swap, but once you factor in the yearly refreshes you'll have to do with the 4L60E and the many potential breakdowns that may occur, in the long run, the 4L80E would probably be cheaper - and a heck of a lot more reliable.

That's just my opinion. I don't know much. When you make your decision though, don't just factor in initial cost. Factor in all the maintenance costs of the 4L60E and the lack of reliability vs. the 4L80E. Take in the big picture. I assume with a truck like that, you've sunk a lot of hard-earned money into it. The best advice I can give you is not to cheap out on the driveline. It'll come back to haunt you.

Best of luck!

 

I am running a performabuilt level 2 in my crew cab 4wd with a nitrous 370 and its holding up fine, granted i don't beat the **** out of my truck daily, and only use about 1 bottle of nitrous a month. I had an issue at first, but i had a new one at my door the same week. and shipped for free. FLT has alot of happy customers, they both have great units. Good luck!

 

I was just on the phone with Toy Shop today and part of our conversation hit onto this subject. The 80 is preferable but I guess its up to you and the size of your bank account.

 

btw, depending on where your located I'd also look into Toy Shop. They're in Pomona CA.

 

If you like the modifying and wrenching like most of us do, the swap isn't too horrible. Certainly expensive (driveshaft lengths will change and so on) but man if you install a FLT 80e and don't have a fubar'ed trans tune or crappy converter throwing **** in your setup, you'll never look back once you install that 80e. Just keep it cool and keep an eye on fluid life and it will keep you happy.

Plenty of info on performancetrucks.net as far as the swap goes. Kysilverado has done a recent KICK *** DETAILED write on the swap if it is somethign you feel you could tackle yourself.

 

You have picked arguably the best builders of performance transmissions in the country. IMO and even they are politely saying forget the 60E. It will not take it.... LONG.

Drop the 60/65E idea and put an 80E in it.

Yeah dependent on what options you go with, level of the 80E, whether you can do the work yourself etc... it may appear the more expensive route in the short term. Chances are it won't be in the long term.

 

No matter whose 4L60E you put in there, I very much doubt that it will last very long behind a big cube forced induction motor in a heavy truck. Do yourself a favor and make the extra effort for the 4L80E swap. If you pay for just ONE extra broken 4L60E (which I can almost guarantee that you will), you could have paid for the 4L80E swap and still had money in your pocket. Trust me....if I painted tranny kills on the side of my truck like fighter pilots do, you wouldn't be able to see much blue left over. I think my tally was 6 4L60E's and now two 4L80E's.

This time around I decided to go with a FLT level 5 4L80E because I personally believe that they are the best choice available. I don't know a lot about the others, but I'm sure that they would be good choices too.

 

4l80e no questions asked you would be dissapointed when you end up going to the 80e after the 60/65 fails which is going to happen with that set up.

 

Carl Rossler is the man for performance transmissions, call him he will not disappoint you and you will get it quickly.

 

FLT 4L80E for the win! With that kind of hp in that heavy truck, the 65E won't last very long. All of the guys over at PerformanceTrucks.net that are running FLT transmissions have been more than satisfied

 

I think you should just buy this tranny

http://www.performancetrucks.net/for...d.php?t=428225

 

Like said I think your asking for trouble with a 65e.

If your truck is close to stock weight its around 47-4800 lbs, that plus 750rwhp is going to be murder on transmissions.

 

I have done the swap as well.... 4l80e Tust me and EVERYONE else YOU WILL BE SORRY IF YOU DON'T DO THE SWAP NOW! My truck is right in the range you are shooting for, the 4l80e holds up to that power EVERYDAY!