tranny problem, help (Not a tranny expert)?(Long)

[tooomuch2]

Have a SB 727 with a stage 2 and big block valve body.

It is fresh (less than 500 miles - so I was told).

Recently, it's started doing this...

Once it's warm.

The tranny Started slipping?(seems like slipping but i'm not an expert).

It does it most Under load (casual cruz up a medium grade hill) in 3rd gear the engine (doing about 40 ish) will begin pulling accellerating while the truck begins to decellerate or not accellerating appropriately with the motor RPM increases.

If I step on it while it's doing it... the RPM's shoot up like I was in nuetral or the tranny is slipping.

If I downshift while it's doing it to 2nd it will quite doing it???

The second time it did it was just tonight and it started bouncing back and forth from 3rd to 2nd then 2nd to 3rd. In other words, started slipping in 3rd, kicks itself to 2nd stops slipping? thengoes back to 3rd and begins to slip?

I did a tranny service on it just 2 days ago (after it did it the first time) thinking that the filter could be plugged. When I cracked the pan I found more metal than I think should be in the pan (especially for new tranny) but I just choked it up to "break in". The fluid was in good shape otherwise (not burnt).

Well needless to say, the tranny service did nothing to solve the problem.

I wonder if my 3rd gear band is shot or out of adjustment (not sure it cn be adjusted). I have a very high stall converter so I thought it may be just not locking up??? Or could it be the valve body?

HELP!!!

[dewme5]

well, it sounds more like slipping in the clutches, not in the converter. What type of fluid are you running. if not type F, then give it a try. it has a higher friction coefficient then dexron. If the clutches are slipping, and only has 500 miles, I would guess that the clutch pack wasn't put together right.. clearances are off just enough to be a problem.

[451Mopar]

Third gear does not use any bands. It could be slipping clutches, but that really does not explain the down shifting unless you are giving the engine alot of throttle kicking down to second.

My best guess is the valve body is messing up. I had one do simular to yours and found a crack in one of the fluid paths in the valvebody.

[Hittman55]

DId the tranny work ok before the rebuild? If not maybe the case is cracked or warped!

I think these guys are right the clutches would be the culpret! Each friction clutch and stator call for .005 clearance each, so If you have 5 like some 727 (mostly early 440) there should be .025 total clearance in the drum, if 4 then .020, you get the idea! If there is maybe only .002 clearance between them the cool fluid could not get between them to disapate heat properly, your clutches slip, get hot, fry! Even if the pan is full of fluid. If the tranny shop was any kind of people they should fix it no questions asked! Look at the trouble they caused you! Most importantly your time and skin! (knuckles). Tranny work is not brain surgery. Once you done them a few times, its no harder than engine work. But I always tried to get a good tranny to began with, the end result will be more reliable.

[AJ]

When it starts to slip in 3rd gear--stop--then try reverse--if it slips in reverse the problem is the direct clutch. (you might have to step on it more in reverse to get it to slip because of the gear reduction) AJ