Heebz

Hello everyone,

So, about a month ago I changed the oil in my automatic transmission. Dropped the pan completely, cleaned the screen, wiped off the little magnets, and filled it back up with new fluid. I can't remember what fluid I used however, but it wasn't factory stuff. Got it from the local NAPA store I think.

Anyways, since then, I've had problems with the tranny falling out of gear at hard stops. I'll be cruising along and I'll have to brake hard (last minute stoplight or something) and come to a complete stop. When I hit the gas to get going again, the engine revs and there is a full 1 - 2 second pause before the tranny goes CLUNK and falls into gear. It happens fairly regularly on hard stops. Soft, controlled stops don't cause any problems.

Anyone have any suggestions/thoughts on what might be causing this? I'm tempted to bring it to the dealer for a full tranny flush, but I want to know if this will cure my problem.

Thanks all!

Heebz
1998 Toyota 4runner Limited. 4x4, Automatic, 6-banger.

TechWrench

I am assuming, that prior to the drain and refil, you didn't have any trans problems? If so, I would suspect first that you have a fluid level problem. Make sure that you check the level with the trans up to operating temp, and on level ground, and idling in park. If the level is good, then you probably have a fluid compatability problem with the NAPA fluid. At this point a complete flush would be a good idea as soon as possible. The longer you drive it acting this way, the greater chance you stand of permanent damage.

Ilovemountains

Last year I posted the same issue. I dropped my pan, replaced the filter and gasket and refilled with that high mileage crap ATF. That afternoon I hit the brakes for a speed bump and rather than dropping into 1st the engine revved up, just like yours. I freaked out! I stopped off at AutoZone and bought another batch of ATF, drained and filled the pan again. This corrected the problem some what but after doing more research I found that draining and filling really only changes 4 quarts of the 16 in the system. I drove it like this for a few thousand easy miles and just 2 weeks ago did a full on fluid swap. It cost about $80 to do it and takes about 1.5 hours. You could do it for $45 but I bought all Mobile 1 full synthetic ATF. Buy at least 16 quarts. I know AAMCO semi synthetic that AutoZone is $3 a quart and is supposed to be really good for the price. I drained my pan and filled it with 4 quarts of the fresh fluid. I then took a 5 gallon bucket and marked it off in 1 gallon increments, the old way filling a 1 gallon jug up and pouring it in, then marking it off! Take your new graduated cylinder pour the 4 quarts of old fluid you drained from the pan in it and place it under the front end. Under your radiator there are 2 hoses they are your Trans cooler input and return lines. I unhooked both of them, and ran them into my bucket, along with another piece of hose I slipped over the nipple that the 1 hose came off of. Start the engine in park and jump out, and watch your marks on the bucket. When you get almost to the 1 gallon line, shut off your engine quickly and add another 4 quarts to the pan. Do this again and again till you have 4 gallons in your bucket. Your AT holds 11 quarts in the transmission lines, cooler and pump and another 4 in the torque converter! Hook the lines back up and make sure they are tight. Start your engine and with it running check your transmission fluid level. Bring it up to the cold level mark on the dip stick. If you do this with the engine off there is a good chance it will look way over filled but that’s ONLY because the fluid has drained out of the pump and back to the pan. My transmission even with 152,000 miles locks right up, shifts SMOOTH, but at the same time very quickly and hasn’t had a problem down shifting since. ANY synthetic ATF isn’t affected by cold temps so the OD drops in about 3 miles sooner than it did before with the mix of crap fluid that was in my Trans. It’s worth spending the $$ on now to make sure your fluid is A. all one brand and type, and B. that it is clean all the way through the system. If you don’t want to drop nearly $100 on Mobile 1 full synthetic I would at least spend the $$ on the semi synthetic. Buy an entire case and run 18 quarts through for a good flush. You don’t need to drop your pan again since you just cleaned that, BUT I would get that fluid swapped out before something goes terribly wrong in there! I figure a transmission shop will charge at least $80 to flush and fill it with basic ATF, if you are willing to do it yourself you can put M1 in for the same price, just my .02 once again! Have a good one and keep me posted, I’m anxious to see how this works out for you! Matt

Ilovemountains

TechWrench
If it ain't broke,
fix it till it is.

AHHH everytime I read that I crack up, so true so true!!!!

TechWrench

I've be 'working' for the Government for WAY to long.............

MTL_4runner

Definately sounds like a fluid level problem to me too.

Ilovemountains

"Close enough for Government work"!

Heebz

Just an update to my problem. I took my truck to Michael's Toyota in Bellevue, WA and had them run a full tranny flush, complete with Justice Brothers cleansing fluids. $160 later.... my problem is gone.

Thanks all

TechWrench

Good to hear the problem is solved, hope it stays that way.

stevrock

Ok, I guess since people are here, I'll ask my question.

When my transmission is cold, I will put the truck in drive and go for the end of the driveway, but then the gears would disengage when I come to a stop or apply the brakes. Then, pressing on the gas or just leaving my foot on the break, the gears will engage again and the truck will get that jolt only an n-bomb would do, without the purposful intent, squealing tires, smoke, or burnout noises.