My daughter'* 91 Grand Prix with around 250k miles started to experience some slipping in first gear when cold. She found that if she put it into park, then back into drive would keep it from slipping that time. I talked it over with a mechanic where I buy my parts, and he suggested trying the Seafoam Trans Tune, that it could be a sticking solenoid. ( I had just changed the fluid, so that didn't seem to be a likely cause.)

I'm not generally a big fan of additives, but I thought I'd at least try it. She'* doing her post-doc work out of state, so I had her pick some up at Autozone and follow the instructions on the can. I was pleasantly surprised to hear from her that it had fixed the problem...no more slipping.

If you experience similar problems, you may want to give it a try.

my friend'* car has a similar problem, but more severe, i usued to slip, now it just doesnt get into drive at all, i got a bottle of seafoam for it, ill let you guys know if it does anything

It CAN help, depending on the exact nature of the problem. And I don't mean the symptom, but rather WHAT exact device inside the trans is causing the symptom. It'* hard to tell without trying.

I can tell you I'm convinced it saved my trans for at least another 3 months before it finally let go completely.

It eased some of the symptoms that were resulting from near-total-destruction-in-progress.

well my friends tranny is probly destroyed, but he figured it was worth a shot, $5 is cheaper than a new trans

It won't 'fix' the trans. It might alleviate some of the symptoms, and it might lengthen it'* potentially short remaining life.

And it also might be the final nail in the coffin.

so if it was a jammed valve, and it cleaned it out, that wouldnt fix it?

It'* hard to say, as it would be a guess that a stuck valve was the problem. In this case, it would seem to be a good guess, but sometimes making one part work better in a tired transmission wil put extra stress on other bordeline parts causing them to go. So far, this has worked. I was willing to try it as it was decision time of what to do with it. Get rid of it, which she can't afford, try to find a good used transmission, rebuild, etc. She would like at least another year out of the car. We're keeping our fingers crossed, knocking on wood, etc.

transmission additives make me nervous