Thread: Hard shift from 2nd to 1st after stop

2004 pontiac gran prix base model. After stopping at an exit or stoplight, trans shifts EXTREMLY hard into first gear. Sometimes it shutter, sometimes it doesnt. Happens randomly wether cold or warm. Found a bunch of stuff on Google ranging from accumulator pump to valve body. Finally threw a p1811 code. Not sure what to do from here. 208k on tranny

Also, threw a P0742 code......fyi

Thanks for your input. I don't know much about transmissions. I've read that they put the 4t65e in everything from impalas to buicks. Aside from final gear ratios, would a used transmission from an impala or buick work? The electronics and programming is my major concern......

http://www.grandprixforums.net/threa...stop-Read-this

After you read all that, the fun part is that the side cover needs to be removed from the trans to access the solenoids.

get a used tranny, install shift kit as preventive measure.

Originally Posted by SaukRapids

After you read all that, the fun part is that the side cover needs to be removed from the trans to access the solenoids.

That's why i put the transtune cleaner in it with an extra strong magnet attached to the outside of the pan to catch anything the clogged interior magnet misses. Run it for a week and then do your filter change and shift kit and then install the extra magnet inside. Screw pulling that side cover. The transmission is already damaged when you notice the bang. This is just to try to make it more tolerable/ band aid. like said above the band aid often works for a long time. Mine lasted years before I decided to change out the transmission.

If I manually downshift into 1st after a complete stop, it never gives me any trouble. I just slide her back up into drive and no shutter. Is this because your are manually forcing the trans into 1st instead of relying on the line pressure?

Could be. Are you thinking of doing that until you can apply a fix?

I'm not sure how long I'd run mine like that, personally. Changing the solenoids costs around $75 for all (much less than a full rebuild), but they're a PIA to get at. I agree that going in that far, a rebuild should be considered anyway.

Originally Posted by s84pearce

If I manually downshift into 1st after a complete stop, it never gives me any trouble. I just slide her back up into drive and no shutter. Is this because your are manually forcing the trans into 1st instead of relying on the line pressure?

Probably. It's the increased line pressure that helps. If i drove my car in manual (tap shift) it would never act up because in manual the line pressure is increased. A tune to adjust the line pressure may help calm it down. you can do a box tune and just ask them to increase it more than they already do. Just throwing out some suggestions.