Thread: Tuning fix for slip-bang from stop?

I have a 2005 Impala that has the slip-from-a-stop-then-bang-into-gear problem. It has been getting progressively worse over time, until it has gotten to the point where it will do it if I'm at a stop for any more than about five seconds. I have read that this is usually caused by fluid leakage around a worn input clutch apply piston.

The one thing that makes it not slip is by manually putting it into 1st gear at a stop, then switching back to Drive as I accelerate. I have also read that this is because manual 1st increases the transmission line pressure enough to overcome the leak and keep first gear fully applied.

So my question is this: Is there a way to program the PCM to apply higher main line pressure when I stop so that it's effectively manual 1st without having to shift into it? It would just be a band-aid fix until I get the money for a rebuild. The car has a column shifter, so it's a real hassle to constantly shift between 1st and Drive in city traffic.

you got any codes popping up from it? shift kits can help a max adapt code.

truth, it dont sound good to me, like rebuild or replace with a used unit time.

how dark was the fluid before the flush? might have put the last nail in its coffin on the flush. best you can do now is a qt of some trans medix type stuff.

get thin clear plastic tubing, bout 6 foot or so. feed it down the dip stick, then to the ground over the fender, suck on the tube and it will keep coming out. suck a qt out into a old qt bottle if you got one, then dump the medix stuff in, so your not over filled.

Shift kits and tuning only increase shift pressure. There isn't anything easy to increase base pressure.

I would try a bottle of Lucas....you may get lucky.

Use Lucas BUT use the "LUCAS FLUID CONDITIONER" quart size bottle. The reg. lucas stop slip will burn your trans in three months or less.

You can also try the along with the conditioner a tube of Lube Gard Anti-Shudder comes in a red 2oz tube. Most good auto parts stores carry this in stock on the chemical aisle shelf.

EDIT:Worst case scenario is you would need a PCS solenoid change and since you already are in there swap out the TCC and shift solenoids. Use the Seafoam Trans Tune before to clean all the valves in the valve body then drain it all out and do the solenoid/switch change then put only Dexron III/VI Max-Life (Made by Valvoline) and you will be ok. Use no additives.

Originally Posted by moddman

Use Lucas BUT use the "LUCAS FLUID CONDITIONER" quart size bottle. The reg. lucas stop slip will burn your trans in three months or less.

What's the difference? I haven't heard of anyone having problems with the Lucas transmission fix.

Originally Posted by wstefan20

I really hope this doesn't come across as negative in any way, but having rebuilt several of these transmissions and knowing several people who do this for a living, I really can't not disagree for the sake of the op.

While I agree with your first recommendation for the lucas treatment to band-aid the system, I cannot agree that "all it needs worst case" is garunteed to be a few solenoid and you're good to go. While I have personally seen that is all that is wrong with a transmission with these symptoms, I think it's a false sense of hope promising that's all it needs. I've seen some pretty strange outcomes and each one is unique. I'm not a parts swapper. While it's true that I recommend replacing all the solenoids while you're in there, I also recommend a full tear down and inspection. I feel telling someone to do a partial job especially if it doesn't fix the whole issue the first time is not right. I've seen slipping being a whole host of issues from the AFL valve wear to sticking boost valve, and the list goes on.

I'm not trying to bash, and I'm not trying to crush the op's dream of a quick fix, but I'm simply trying to be realistic about the situation having personally dealt with this several times and learning from doing it the wrong way and not taking the time to fully inspect the system. There is simply no reason not to perform a full inspection off the valve body, channel plate, clutch packs, chain, and other components while it's out of the vehicle (don't get me started about the whole trying to drop the subframe method, it has it's place, but I'd rather do open heart surgery in an abandoned Denny's). The parts aren't expensive, and you really don't want to be tearing into it a second or third time to fix the issue.

imho.

I certainly don't expect a miracle cure, just something to get me by for a few months until I can replace it. I don't have my own garage to do a teardown myself. I'll just get it rebuilt. Probably have to pay someone to put it in for me too, unfortunately.

Lucas transmission fix is like "glue consistency" and will gum up your valve body and o-rings and make them stick eventually and burn up your trans. The fluid conditioner while similar it is a better product to make the fluid into a better fluid that is in there with "conditioning additives" much like Max Life but very concentrated. If you try those two products you "might see" results. I have seen the Lucas Trans fluid conditioner at Meijers and both products (the Lube Gard anti-shudder) at Oreillys and maybe Advance or Autozone (<----not sure on the last two places). Try them and run the car in all gears with foot on brake two times ten "actual" seconds in each position. Suck some out first (one quart) as Scotty said to ensure NOT to overfill then add products. Drive the car around the block a few times so you stay close to home and if you feel adventurous take it on major streets after if "so far so good". Its worth a shot but in the end your only out ten or twelve bucks. As wstefan said this is NOT a guarantee FIX but ONLY trial and error if your on a budget it doesn't hurt to try first.

I have seen the Seafoam Trans Tune at Meijers as well as Autozone. This either you can try first before anything as it cleans the PCS filter and the valve body very good w/o taking anything apart OR try this before you take apart to tear down the trans if your doing the solenoid/switches/TCC (torque converter clutch solenoid) fix if you get a hold of someone w/ a good scanner that reads PCS (pressure-control) solenoid/trans data and can read/reset trans adapts when you end up seeing what your trans is doing before to diagnose it and after you tear in to it to verify the fix and reset/relearn the trans adaptations in the TCM (trans control module).

Hope this info leads you in the right direction to getting your trans to run correctly. Try these things out and let us know how it turns out.

Originally Posted by moddman

Try these things out and let us know how it turns out.

Okay, I bought a 16 oz bottle of the Seafoam "Hydra Trans Tune" (as they call it now) and tried it out. Preliminary results are good! I sucked out some of the old fluid and added the Trans Tune. Started up the car, let it idle for a minute to mix up the trans fluid, and then started driving around town to let it go through all the gears. I drove for about 20 minutes. The transmission only gave me a little bit of slip on the first light I came to, and every stop and start after that there was NO SLIPPING. The car is my wife's daily driver, so I told her to take notice over the next few days and tell me if the slipping stays away or comes back. But my initial experience suggests that it may have actually worked!