1999 montana transmission issues

[gtnmuddy]

Somewhere I thought I read a post about my problems.

About 6 months ago the montana started shifing hard between gears. I stopped at a Napa to get some Lucas trans fix fluid and when I got back into the car the tranny worked great. That was about 30k ago. Tonight my wife informed me that the trans was winning and shifting hard again. I drove the car and it was the same thing that happened before.
After the car sat for about 30 minutes I drove it again and it is working flawless again.

Any ideas on the problem? hope it is a cheap one

Larry Barnes

[GTP Dad]

When did you change the fluid and filter in the transmission? It is possible that the filter is blocked and that the fluid is having a hard time getting through. I would change it if had been more than 30K miles and add a can of Sea Foam Transmission Additive or a bottle of Lube Gard. Both are excellent and can help transmission performance. If this doesn't help you may want to have a tranny shop look at it to see if there are any sticking solenoids. They will use a trans capable scanner.

[mhall02]

My in-laws had this happen on our 99 Montana when it was under their ownership. It was under warranty and at about 60,000 miles. I think it ended up being rebuilt but since it was warranty work, I'm not sure what the cost would have been. I'll try to look through the paper work and see what they did. It has shifted nicely since then, I'm now at 146,000 miles. Actually, if I remember correctly, my mother in law was driving it to work one day and it started doing it, so she drove it straight to the dealer, didn't turn it off when she got there and had them drive/diagnose it. How many miles do you have on your van?

[MT-2500]

Originally Posted by gtnmuddy

Somewhere I thought I read a post about my problems.

About 6 months ago the montana started shifing hard between gears. I stopped at a Napa to get some Lucas trans fix fluid and when I got back into the car the tranny worked great. That was about 30k ago. Tonight my wife informed me that the trans was winning and shifting hard again. I drove the car and it was the same thing that happened before.
After the car sat for about 30 minutes I drove it again and it is working flawless again.

Any ideas on the problem? hope it is a cheap one

Larry Barnes

As said have a look at the filter and fluid.
Also a good time to get it on a good engine/transmission capable scanner and see what is going on.
A lot of good info in there.
Check for history codes.
If any codes post back codes.
MT

[truc0011]

Originally Posted by gtnmuddy

Somewhere I thought I read a post about my problems.

About 6 months ago the montana started shifing hard between gears. I stopped at a Napa to get some Lucas trans fix fluid and when I got back into the car the tranny worked great. That was about 30k ago. Tonight my wife informed me that the trans was winning and shifting hard again. I drove the car and it was the same thing that happened before.
After the car sat for about 30 minutes I drove it again and it is working flawless again.

Any ideas on the problem? hope it is a cheap one

Larry Barnes

I am having the same problem. I have harsh shifting conditions, then eveything seems fine. Eventually I got a code of P0758 which is for the 2-3 Shift Solenoid, I haven't had time to try and fix it though. I'm thinking of replacing the 2-3 solenoid and see what happens......maybe even the PCS.