camarosource

iTrader: (1)

1992 Camaro Z28 with MXO Automatic 4 speed tranny with Overdrive..

Seems my tranny is shifting at quite a high RPM I think.. Anyone know what RPM the car should first shift if you were at a stand still and just slowly starting to drive?

I have been able to get a video of what *I* am experiencing..

Video #1 - If you listen closely you'll hear what sounds like the tranny is TRYING to get to the point to shift but is slow at doing it. As if the engine is revving too high before it shifts.. http://media.putfile.com/100_9778

Video #2 - MUCH better example..

0.15secs - 0.23secs : Can you hear like the engine is revving really high and the trans sleeping when it should be shifting??

0.29secs -[end] PERECT EXAMPLE! You'll notice just before the end of the video the engine is really revving (needle getting awfully close to the yellow!) for a long time before the tranns shifts and you see rev needle bounce back down.. http://www.camarosource.ca/temp/Production%202.mpg

Does this look and sound NORMAL to you guys??? I've had the car since 1998 and NEVER had this problems.. It's really bad going up hill where it is in gear, then perhaps slip down a gear cause the engine revs and I have to put my foot really into the gas pedal to get it to move!!

Seems to do this more as the engine warms up.

Fast355

iTrader: (2)

Looks like the engine is just falling off, before the transmission shifts. Needs a little more power to get to the WOT shift point, but is being strangled by something.

When was the last time you had a tune-up. Hows your timing, what about your fuel pressure, etc.

I do know that my stock 700r4 behind my carbed 305 shifted at 4,800 RPM @ WOT.

Supervisor42

That is the unmistakable sound of a transmission slipping.
You should pull the pan and check it for debris.
The rpm should only go up with vehicle speed.
test video.

camarosource

iTrader: (1)

Interesting.. Could this be a matter of fluid being topped off? What's the "Test video" doesn't work for me.

Supervisor42

It could be if the transmission has a leak and the fluid is low.
Test video is a video of my 700R4 that I'm trying to get the shift points right on. Also a test of the hosting service.

dimented24x7

iTrader: (2)

Id definatly check the fluid level, especially if its worse around turns. Could be exposing the pickup.

Other then that it sounds like its possibly toast and in need of a rebuild.

camarosource

iTrader: (1)

hmm.. It says "The video you have requested is not available." for me..

Supervisor42

I wasn't gonna say THAT!
Video not available for a little while...

camarosource

iTrader: (1)

Ok. Went for a test drive. And it DOES in fact appear to do it worse while going around a corner slowly as you approch and trying to go at a decent speed near the end of the turn and continuing straight.

Trans was tuned up and oiled in June. I cannot tell how much oil is in it as I can't figure out how to read the dip stick. The oil is smearing on the entire reading at the bottom and almost to the bottom of the "S" bend is. There appears to be no thicker part and I tried like 5 times befoe giving up.

z28 NyC

Make sure that when your checking your the tranny fluid the car is running, hot, and it park.

camarosource

iTrader: (1)

Yep, did that

Randy82WS7

make sure the TV cable is set correctly and in good shape., if so then uhmm

il let someone else say it

i dont wanna

good luck

:O

Supervisor42

It works now:Video: 1-2 WOT upshift too high 2-3 WOT upshift too low. (below 6500)
I have to pedal shift it or this happens:
Video: You can hear the rev limit hit twice at 6700.
These are outtakes due to glare on the tach. Better videos to come.
My transmission problem. I need to lower the WOT 1-2 upshift and raise the 2-3 upshift. Redline and rev limit set at 6700.
Any transmission guru's out there?
(and please don't say "adjust the TV cable")
Turndowns only after the headers. My neighbors just love me...

iggy1991

Definately sounds like tranny slip. When mine went out it wouldfree rev, as if in neutral and would catch the next gear and rev back down. Only did it in 2 to 3 shift and wouldn't you know thats want went out on me, 3rd and OD.

I agree with the other guys about the fluid level. Add a quart cause it can't hurt and see what happens.

camarosource

iTrader: (1)

UPDATE: More news on the transmission problem:

I went to my local (like family) mechanic shop and they spent a few hours helping to diagnose the problem.

1. The last place (Transmission shop for a transmission flush, change filter, and fluid) I took the car in (June of this year) put WAY too much fluid. On the tip stick, it was reading RIGHT up to the "S" bend on the dip stick (appox 1 1/2" higher than the most amount)..

Removed excess trans. fluid to the correct amount. Still the same problem.

2. Mechanic went on test drive with me and trial and error with the gear shifting shows this ONLY OCCURS WHEN IN OVERDRIVE (D).

Reserve, 1st, 2nd, Drive "D" is PERFECT. Put it into OVERDRIVE and it's as if my gas pedal is effecting the REVVING of the car rather than powering to the wheels.

He is thinking it is more along the line of a SPEED SENSOR or some sort that deals with the engine knowing when to change into OVERDRIVE. He suspects that the car is going into OVERDRIVE WAY too soon (almost instantly) before the transmissions actually is.

Your opinion? What sensor would this be?

dimented24x7

iTrader: (2)

Been awhile since Ive done any troubleshooting with a 700-R4 but it sounds like the forward clutch is bad and/or there is an internal leak.

Definatly dont want to quote me on this. Been awhile. IIRC, in 1-D, the overrun cluches are engaged and this provides a backup for the forward clutch.

camarosource

iTrader: (1)

ALL Gears work perfectly EXCEPT Overdrive (D).

Could this still be a clutch?

Supervisor42

You're probably right. Anyway, the answer is always the same. Change fluid & filter, check the shift linkage and the oil cooler, then remove & rebuild.

dimented24x7

iTrader: (2)

If you mean that it only slips in all the forward gears in OD then its a possibility that the forward clutch is bad (i think). As far as the fluid goes, it should be a rock solid line on the stick with no foaming or bubbles.