Transmission not shifting properly

1994 CHEVROLET SUBURBAN

160,000 MILES • V8 • 4WD • AUTOMATIC

FREEDOM#1

MEMBER
1 POST

Hi, my transmission started shifting to a lower gear real fast almost bogging out the engine at times but otherwise it runs great. However, now it's starting to shift up and down, what could it be?

Jun 8, 2022 at 2:13 AM

SQM

✓Experienced Mechanic
6,383 POSTS

Hello,

One of the first things you want to look at is the transmission fluid.
Make sure it is at the correct level and in good condition. Contaminated or old fluid can create shifting issues.

Does this happen regardless of temperature or more when cold?

These transmissions tend to have this type of shifting issues after there is considerable number of miles on them. The best thing to do many times is to change the fluid and keep it clean. That can reduce the symptoms.

Take a look at this helpful guide:

https://www.2carpros.com/articles/automatic-transmission-problems

Let me know of any questions.
Thank you.

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Jun 8, 2022 at 8:27 AM

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