Transmission does not engage in gear unless you give it some RPM's

THECUBICBUICK

MEMBER
1989 BUICK LESABRE
3.8L
V6
2WD
AUTOMATIC
130,000 MILES

So one day I was driving on the highway and my gas pedal was stiff at about 40 mph so I pushed the pedal a little further and I heard a loud bang and the car seemed to have gone into one single gear. Well, once I got home I tried driving it again and it wouldn't shift out of first. So I tinkered with the transmission cable and it started shifting again, but you had to give it some gas before it would engage in gear and currently sometimes when you sit in drive parked or turn the A/C on the whole car shakes. It shakes also when you don't give it enough gas to get in gear.

Thursday, October 15th, 2020 AT 11:52 PM

1 Reply

ASEMASTER6371

MECHANIC
52,796 POSTS

Good morning,

This sounds like the filter is clogged in the transmission.

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

I would drop the pan and change the fluid and filter. This is the most likely cause.

https://www.2carpros.com/articles/how-to-service-an-automatic-transmission

Roy

1. Raise and support vehicle, then position drain pan under oil pan.

2. Remove front and side oil pan attaching bolts, then loosen rear pan attaching bolts.

3. Carefully pry oil pan loose from transaxle case and allow fluid to drain.

4. Remove remaining attaching bolt, oil pan and gasket. Thoroughly clean pan before reinstalling.

5. Remove and discard screen and O-ring seal.

6. Install replacement screen and O-ring seal, locating screen against dipstick stop.

7. Install gasket on oil pan, then apply Loctite 242 or equivalent to oil pan bolts to prevent leakage.

8. Torque oil pan bolts to 12-13 ft. lbs.

9. Lower vehicle and add approximately 6 quarts. of fluid.

10. With selector in park, parking brake applied and engine at idle speed and operating temperature, check fluid level and add fluid as necessary. Do not race engine or move shift lever through ranges.

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