Stock 4L65 vs Built 4L60 vs Built 4L80
 

So I have a 2005 Silverado SS. It has been my daily driver since I bought it in 06 and it has 85K miles on the engine and Tranny. My SS is going to soon be just my Play toy. Im planning on only driving it when the weather is nice and I will drive something else in the winter.

I have been saving up some green and I would like to Turbo my truck. Im not looking to have a 10 second truck, just a little more umph. When its all said and done I would think I would be in the 500-550hp range.

Well the last thing I want to do is turbo my truck and then blow my tranny.
So Im trying to figure out which way to go. I have talked to a few people on other sites and I figured I would see what you guys think. I have searched this site but have not found the answers I am looking for.

Do you think a Stock 4L65e with a shift kit and servo upgrades will be able to handle 500-550hp? Some people I have talked to said I should be fine and others say my tranny wont last long. I also do some minor towing if that makes much of a difference

So my next option would be to put in a built 4L60e. I was looking into FLT's Level 3 or 4 4L60e. That should be the easiest option and should be and easy swap. I have a buddy who said he could easily help me swap out my tranny. But I have had some people say that since it is still a 4L60 (even though its a FLT) its still a POS 60e and will not last.

So the much more expensive and difficult option would be to swap in a 4L80. I know that it is much more difficult since it is not a direct swap and I have heard the crossmember must be changed, and there are a bunch of extra parts you have to add to make it fit.

So I guess my big question is will a Stock 4L65e with a shift kit and servos be able to handle 500-550hp?

If not Is it really worth the extra money, and Hassle to swap a 4L80? Or is a FLT level 3 or 4 4L60e plenty enough to handle 500-550hp?

80e swap isn't as hard as it sounds.

https://www.performancetrucks.net/fo...-4l80e-424904/

If its not a daily driver I say keep the 65. If it does go you will have the time and funds to fix/swap it.

You asked for our opinion/advise.. so here goes mine haha

Since you can afford to have some down time, id go ahead with the 80E swap. Junkyard or built, either one. Stock with a Shift kit and a good tune makes a good difference.
I think the adapter for the Xcase is only about $45? its been awhile since i looked so im not sure on that..
The trans crossmember is a simple mod if you got a welder.

Then you should be ready to rock! Peace of mind having a stout transmission under there.

:stupid:Well said.

Ive already played the 60E game.. it sucks!!
ive put a bunch of miles and tons of abuse on this JY 80E and its still kicking. Now another turbo is goin on so its gonna get abused even more towing way more than i should :D

60es suck behind anything with torque, turbos and 60es dont go together. At 500hp the 65e will hold it but how long is a different story. If you put in alot of torque management in the 2-3 shift it should hold for a while, but you will always worry about it.

He has a NVG149 T-Case(AWD), good luck finding a adapter for cheap. You cannot just change the input gear like you can on the manual T-Case. Same T-Case I have.

If your looking to put a built 60 in your truck you will need to think about levels much higher than the 3 or 4. Personally I would not build you a L3 or 4 trans for your vehicle. I would suggest a billet output shaft, billet pump rotor and one of the new sonnax input drums that are on the market. No doubt an 80E would be the best option and you would have to look into getting one with the splines cut down to be used with your transfer case. HTH Vince

If you can afford some down time, you can have your transfer case input gear modified to work with the larger 80E output shaft. No way I'd want an output shaft that's the same size as the 60E output shaft, they break too easy.

Hum. Now i didnt know that. Can a xcase like a nv246 or something bolt right in? Wire up for the encoder motor?
I dont know much bout that just thinkin outloud.
The 246 come behind 80e's i think. Unless i got my numbers wrong.

You'd need a switch, a TCCM, front diff actuator & extension housing, the transfer case, and the harness. I've seen people remove all that stuff to go AWD, but I've never seen it reversed.

Vince, I've been away from PT for awhile. This is probably my 1st post, so I've been outta tha game, the loop, How long has this Sonnax imput been out, is it an imported unit, but just better than stock?

Lastly, if it's better, why or what makes it so? :judge:

I believe the Sonnax is claiming to be stronger than the Beast, partly because it is radiused at the collar, rather than cut to a 90* like the Beast. Only a couple of builders up here have used them, so nobody up here has really proven them yet. But, I've seen a broken Beast first-hand, so.......

BTW, welcome back buddy! :)

Roger, you are referring to the Sonnax Smart Shell which is their upgraded sunshell. Vince mentioned a new Sonnax Input Drum. Not certain but I believe it is just a modified stock input drum with a collar that has been machined to accept more clutches and a different retainer. Sonnax - Aftermarket replacement transmission, torque converter, and high performance automotive parts Vince, please correct me if I am wrong.

Thanks everyone for the Advice.

I will have too try to weigh the pros and cons of going to a 4L80 or keeping the 4L65. I guess I will have to talk to some of the guys on SilveradoSS.com to see exactly what parts I need to do the 80 swap and see if it is something I can do myself, because I really dont know of any shops in my area that can help me

a 60e-70e variant CAN withstand the power. I've seen it done many times. Also seen supposed built transmissions not able to hold much more power than stock. A 60e, if built correctly and tuned correctly can last behind an 11 second truck...

If you're willing to spend some serious jack on a 60E then yeah, you should be able to have one put together to do what you want, but truthfully you'll be about the same $$ wise doing an 80E.. Don't consider anything less than a builders top of the line unit for what you're asking. 550whp in a tank SSS will chew up and spit out 60E's like bubble gum, unless it's done right, no shortcuts and no expense spared. Big cooler, billet converter etc.

Your at the power level that a 60 would still work for you, but if you're wanting to do a trans swap once and be done, do a mildly built 80E and enjoy some reliability and not cringe every time you want to run the truck hard.....