Trany Problem

[broddog28]

I have a 99 Malibu with about 150,000 miles on it. The problem I am having is that when ever I put the car into drive from park it shifts hard and slams into gear. It does the same thing when I shift it from drive to reverse and vice versa. Do I need a new trany or is there something I can do to save this one?

Shawn

[BNaylor]

Originally Posted by broddog28

I have a 99 Malibu with about 150,000 miles on it. The problem I am having is that when ever I put the car into drive from park it shifts hard and slams into gear. It does the same thing when I shift it from drive to reverse and vice versa. Do I need a new trany or is there something I can do to save this one?

Shawn

Try changing the tranny filter and replacing ATF first if you've never had it done before. With 150K miles you are probably due a rebuild. I believe that your tranny is 4T45-E. I would not recommend getting a flush service with the amount of mileage.

Another step would be to have an ODB-II scan done on the car and see if you have any generic or manufacturer specific DTC codes tranny related. Many of the error codes will not give you a SES or check engine light but the computer holds them for reference. Good luck!

[mikept03]

Originally Posted by bnaylor3400

Try changing the tranny filter and replacing ATF first if you've never had it done before. With 150K miles you are probably due a rebuild. I believe that your tranny is 4T45-E. I would not recommend getting a flush service with the amount of mileage.

Another step would be to have an ODB-II scan done on the car and see if you have any generic or manufacturer specific DTC codes tranny related. Many of the error codes will not give you a SES or check engine light but the computer holds them for reference. Good luck!

It's still recommended to change the transmission fluid and filter at 100k as the manual says, right? I'm nearing 100k on a 1998 and the fluid has never been changed, so will changing it do any harm?

Thanks

[BNaylor]

Originally Posted by mikept03

It's still recommended to change the transmission fluid and filter at 100k as the manual says, right? I'm nearing 100k on a 1998 and the fluid has never been changed, so will changing it do any harm?

Thanks

I don't believe that changing the ATF (Dextron-III) and filter will do any harm especially if you are nearing the 100K mark. Regardless, the ATF fluid breaks down over a period of time. Actually GM does not recommend doing any tranny service on the 4T45-E unless you experience problems, etc. However, GM does recommend doing the service at 50K miles and 100K miles if one or more the following conditions occur:

Heavy city traffic where outside temperatures regularly reaches 90 degrees or higher

In hilly or mountainous terrain

Frequent trailer towing

Taxi, police or delivery service

In my case, we are at 90 degrees regularly from June - September and drive primarily in city traffic and therefore, did our first tranny service at 50K miles. The upshifts and downshifts felt better with new ATF and filter.