transmission troubles
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transmission troubles 2002 chevy trailblazer
I mashed down on thew throttle, and at about 30-40 mph, there was a loud bang. At that point, i rolled to a stop with no forward movement. I tried 2wd, 4wd, still nothing in D. I shifted to 2, and was able to move forward. I have to put it into 2 to take off from stop. once above 30 mph. i can manually shift into D, and it holds, unless i drop below 30 mph, then i have to manually shift down to second to get it to catch, and go again.
I mashed down on thew throttle, and at about 30-40 mph, there was a loud bang. At that point, i rolled to a stop with no forward movement. I tried 2wd, 4wd, still nothing in D. I shifted to 2, and was able to move forward. I have to put it into 2 to take off from stop. once above 30 mph. i can manually shift into D, and it holds, unless i drop below 30 mph, then i have to manually shift down to second to get it to catch, and go again.
^^^ yep,blown forward sprag. Starting in 3rd or 4th,the sprag does the work. Starting with shifter in 1st or 2nd,the overriding clutches take over and the sprag plays no role. I drove my Z for 4 years that way,it took that 4 years to blow the 4th gear clutch,then replaced the tranny with a used one.
TECH Junkie
Joined: Nov 2013
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From: White Bear, Mn
^^^ yep,blown forward sprag. Starting in 3rd or 4th,the sprag does the work. Starting with shifter in 1st or 2nd,the overriding clutches take over and the sprag plays no role. I drove my Z for 4 years that way,it took that 4 years to blow the 4th gear clutch,then replaced the tranny with a used one.
The sprag is not engaged in 4th.