Finally back up has arrived.... Both transmissions have their strong and weak points...gear ratios being biggest downfall of the 80.... 60 the 3/4 clutch and if they are not built properly especially in higher power applications both will fail... I have seen 80s that were taken care of have more issues than some 60s that werent... Hell i had a 95 2500 with a bone stock 454 and 4.56s that in the four years i owned the truck ate 3 4l80s my 99 with the 60 and 6 inches of lift.... Ive had for 15 years... Ive put 3 transmissions in first one was to use the extended warranty i had which i had felt was a waste of money.... Other two were after id sold the truck and the idiots i sold it to beat the living crap out of it..... And then theres my ex wifes 07 with 213,000 on it never done anything to the trans and she beats the hell out of it and the fluid is still nice and red and smells like fresh trans fluid.... Again both trannys have their place and this arguement can go on for days.. But the 60 isnt for everyone and neither is the 80.. Welcome to opinions and experiences....

 

Sounds like i could get away with a 60, but 80 is a better choice. So.....whats next? Crossmember, harness, ds...... whos got the best bang for the buck on an 80? What am i gonna have wrapped up in those extras?

 

there is a fix for the 3-4 clutch now. sonnax drum. My transmission has one did I mention it's for sale? buy it and free me from the urge to go buy another project just to have something to stab that trans into LOL

 

Have my own ive built waiting to go in, and id be willing to bet yours is 2wd...

 

Agree...

 

Well I've had 2 Silverado one which was a 4.8 with 22' wheels that I had to 4l60e rebuilt 90xxx and I didn't spin the tires or really drive it hard from a dead stop either. Now I have a 5.3 with a Procharger, long tube header for only a few hundred miles of driving and I feel this 4l60e has about had it. at 78xxx with 22" wheel also. I think if you keep it factory from head to toe, you might be OK.. Other then that. Time for a 4l80e, which I will be doing in the next week or so...

 

Didn't read all the posts but the thing that's going to kill a 60e before you get to 500hp is the weight. If your 4wd and have big tall tires, that's a lot of weight to get moving and it's even harder on the trans the more power you make vs a lighter car.. People brag about going 9s and 10s with a 4l60e in a fbody but that's a 3500lb car not a 5500-6000lb truck.. A stock 80e should have no problem at 500hp..

 

Yes and no.... My 99 has a 6" lift on 110-120lb 35s and has been since about a year after i bought it...and i have not driven it like a grandma, theres a reason i have mud caked into the frame....

 

I agree, but i did go over a year in a full weight 2003 RCSB running 11s with over 600 rwhp on a BONE STOCK 4l60e.. i kept it cool and very regular fluid changes. It was tuned and thats it. I say that because it can be done and especially in a built 60e. I personally dont like an 80e, but there is no doubt its strong and its a great transmission... since ive built a few.. but i believe most people dont NEED an 80e. I just get tired of seeing people bash a 60e and act like the 80e was blessed and touched by the hand of Jesus! lol

 

I tuned a Duramax with a 4L85E behind it that is holding up to over 800 ft/lbs of torque with the only transmission mods being a shift kit and deep pan. The thing has held up over 180K miles since tuned and had around 150K on it when tuned. LOTS of heavy towing involved as well.

My point is you can build a 4L80E practically stock, put a shift kit in it, add the TCI low gear planetary set and a good converter and be well ahead of ANY 4L60E build!