Overdrive problems...

[Chris]

Hello all,

I am having a problem in the last couple of weeks with my transmission not doing anything when I go into overdrive when passing on highway or quick take-offs that want to stay in low gear.

2002 Grand Prix GT, with 211,000 kilometers (131,000 miles) on it.

Symptoms:
Stepping on the gas while moving (WOT for instance) causes the transmission to downshift - RPM's hit 4500-5000 but there is no gear catching. Just high rev spinning. I must allow the engine to slow by itself before it'll catch a gear.

Stepping on gas from a standstill causes the same thing. RPM's stay high until the throttle is let off enough for it to kick into gear. The first time scared the crap out of me, I had no movement and my engine sounded like it was going to blow up!

No other symptoms that I can feel/hear... taking off of the line normally is fine. It seems to shift through all gears, both up and down when driving normally. Only when I step on it does this happen.

Recent work done on the car:
Two months ago I did a transmission pan drop and fluid/filter change (not flush). I did end up putting Dexron 6 into it after doing a bunch of research and reading it as fine to do. Fluid looked "okay" coming out of it, there were no large particles, just the standard silt on the magnet.


I assume that there is a problem that needs to be fixed, I'm just looking for advice on where to head. I really hope that I don't need to rebuild the tranny... haha, but you never know I guess.

Cheers,
Chris

 

[Gregorius]

Did you do a post-mortem on the trans filter to look inside?? Does the tranny Whine all the time???

 

[Chris]

I didn't take a look in the filter. In hind-sight it makes sense and I probably should have checked. There were no problems before I made the change, so I didn't think to check the filter when I had it. The transmission was working great, I just thought it was probably time to change it because of the high mileage and I can't be certain if the previous owner had done it. I've had the car for over a year, and it had 110k kilometers on it when I bought it (68k miles).

There is no whining sound from the transmission that I can tell.

 

[Gregorius]

I didn't take a look in the filter. In hind-sight it makes sense and I probably should have checked. There were no problems before I made the change, so I didn't think to check the filter when I had it. The transmission was working great, I just thought it was probably time to change it because of the high mileage and I can't be certain if the previous owner had done it. I've had the car for over a year, and it had 110k kilometers on it when I bought it (68k miles).

There is no whining sound from the transmission that I can tell.

Wish I had an easy fix for ya. There really isn't one. These trannies are a weak spot. They can die after 70k miles of relatively normal use.

It is possible to find a cause for a problem, pull the tranny, replace a $50 part, put it back in, and have a $30 part go out 2 weeks later. Rinse and repeat. It's too much crap to go thru. When one part fails there are 4 other things that are ready to die also.

Been down this road. Get a rebuilt unit and put it in. Is Trannyman still here ??:th_mechanic:

 

[Chris]

Thanks, I appreciate the feedback.

I've begun to wonder if it's my first gear that is the problem...
Since it happens when I step on it from a standstill, and perhaps it's dropping down that far when on the highway, into "passing gear"...

Too much power and it's slipping? But slow acceleration and low power enough to engage?

Hm, it may be time for a trip to the local Mr. Transmission to see if they'd know.

Cheers!
Chris

 

[beno420]

mine goes 1 2 3 gear great then only goes into drive (4th) if you let of the gas BUT then as soon as you give it gas its back in 3rd gear weird if anyone has had this problem let me know or if you have any imput. thanks