captian kirk we have a problem, the 700 powerflow is a disaster
(3.06-1)x.30=.62+1 or the second gear ratio. if your motor makes 300lbs. of torque the overdrive in your trans will see 900+ lbs. of torque in second. with this imfo you should see that no one can change how it works which means you are stuck with the best trans amco ever had. l do not have an answer to the problem just an understanding how it works. l have nothing to sell or a fix, just an explaination of the problem. no hard feelings just good luck

 

john kilgore,
Are you saying 2nd gear is the weak link in these transmissions?
The majority of troubles don't seem to be 2nd gear related though.

The only real problem I have had with my 4l60 was late shifting on the 2-3 which I figured out eventually.
Steve

 

What the hell is it because I'm having the same problem? I've changed my shift times to make it shift quicker, it helps greatly but it still shifts a little slow.

 

I think my tranny is starting to slip too, but i'm hoping it completely go out for a while. Has anyone used the Maximum Evil 4L60E from ls1speed? They advertise that it will hold 850rwhp 800rwtq, does anybody know if this is true? I'm gonna be running around 450-475rwhp and plan on spraying an occasional 250shot. Would the Maximum Evil work or should i look into something different? A TH400 is not an option, OD is a must.

 

Art Carr once made these claims (BS), and as far as I know, there is really nothing out there that can go for 200/300+ quarter mile runs at the claimed HP (750 - 800 HP) & at least 3,200 pounds total weight & last. The real story, is that with what is available at this point in time, 650 HP is the "realistic" max. & have some sort of transmission life at a somewhat reasonable cost. I'm sure that "someone" has made SHD parts for these units, but at a astronomical cost, and not made available to everyone. Believe me, if I could improve on what is out there now, over what I am doing presently (at a reasonable cost), I would do it, and pass it on like I have always done. I have never believed hype from Art Carr, or anybody else for that matter, just what works. Do you want to know a "secret"? there are no secrets, a lot of common sense, & a lot of hard work.......

 

The only way to know the exact parts that will live under high hp/tq is to buy a Rossler or equal and take it apart.

 

So is 475rwhp and a 250 wet shot to much to ask out of a built 4l60e?

 

Maybe not for a pass or two, but................ yes.

 

I don't street drive anymore but my FLP manual Valve Body 4L60E lasted a whole season full of 10.7-10.9 passes at 3350 lbs. I brought it to Chuck at FLP for a fresh up and it was still good.
My experience has shown that if you don't down shift these tranmissions while street driving (or any full throttle down shift) they will last a lot longer.
I'll be giving it a try in the Super Stock Class this year. Hopefully it will hold up to some low 10 to high 9 sec passes.

 

I had set my shift times to 0 and had run it like that for quite some time. My thinking was it would make the trans shift quicker. Well if I ran the car with the blower belt off it would shift fine on the 2-3 and right on time. But put the belt back on and double the power and no more 2-3 shift no matter what rpm or mph I set the 2-3 at. I programmed in a 5000rpm shift with mph extremely low just to get it to shift at 6400rpm. It seemed the more power I made the worse it got.

This just made no sense. It was NOT slipping on the 2-3. It simply would not shift or it was way way late from what I was commanding. The 1-2 would shift a bit late but was no where the problem my 2-3 was.
I then put the shift times back to stock(.500) on the 1-2 and 2-3.
Raised the mph and set rpm to 5800.
Guess what, it now shifts perfectly and hard right at 5800rpm on the 2-3 with 11psi boost. I was quite amazed at how my "performace" tuning of the shift times at been the entire problem.
I use a max shift retard of 10' advance. This kills some power during the shift but does not shut down the motor either.
I also overfilled the stock pan by about 1 qt which seems to help under heavy accleration.
My trans is a stock 98 4l60e with 15K miles and a transgo kit that's been in it for the last 10K.
I have also run this transmission with full manual solenoid activation for about 50 175 shot n20 runs before I went to the blower.
But I don't have a ton of slick runs with this car. Most all have been on dragradials with best 60fts of 1.62. So tire spin has probably helped this sucker live.
Steve

 

i have a built 4l60e from rock on transmissions
there out of denton texas and they have a web site
this tranny is flawless doesnt miss a lick.
they have a web site too
i think it is www.notasponsor.com

 

That very interesting I have the late 2-3 shift while spraying but I'm only spraying a 100 shot and I don't have a shift kit. My tranny is all stock except for the TC. All my nitrous runs have mostly on ET streets( with a fried posi) and about 6 passes with the ET dragradials. I running low 7's in the 1/8th but I think it would be lower if I could fix my 2-3 shift becuase my window switch shuts the nitrous off at 6000 rpms. If I change the the shift point to 5800 rpms I would be spraying through my shifts, I don't want that. This thread is best info so far on my problem. Need more info please!

Bryan

 

how often do you replace your clutch?