Finally used up the last of my Dex III hoard. After a little searching here, ended up doing a change with Valvoline Dex/Merc. Just fluid, not filter, that was done about a year ago. No issues before the change. Anyway, after putting the Dex/Merc in, nothing is right... Shift points are way high, feels like there's some slip, shifts harsh, etc. Is there a better alternative, or an additive that I should be using? I seem to recall someone on here using ATF+4, thought that was for jeeps, is that a better choice than the D/M?

 

Try changing the filter. New fluid loosens old deposits. Dirty filter preventing enough pressure to shift into next gear. Blow out the trans lines and tank inside radiator. They seem to collect sludge. Something is keeping the pressure low that is overcome by higher rpms. Did you analyze old fluid for particles, flakes? Any in it? How many miles on the trans? Have you adjusted kick down cable?

 

Yup, will most likely have to suck it up and do the filter, such a PITA was hoping to avoid it. Changed the fluid and filter about a year / 18K ago, and the fluid came out looking surprisingly like it went in, lovely crimson hue, excellent clarity, and pleasing bouquet. Trans has about 120K on it, kickdown cable is adjusted per RAVE procedure & messing with it only seems to make matters worse. Thanks for the advice on blowing out the tank, hadn't thought of that. All this started when the new fluid went in, which was just a spill, fill & repeat x2 exercise.

 

Well, should be interesting when the trans lets go of the pan...... I blew out the trans tank on my radiator and I can't repeat what I said.

 

I'm using Mag1 synthetic ATF. Haven't touched the filter, I only do drain and refills. I'm actually due for another.

 

When you say blow out the trans tank.... What process are you using to blow out the tank ? I need to change the fluid in my trans and this sounds like something that I should consider.

 

Just drain and refill.

 

Consider draining fluid and replacing with Penzoil "ATF for vehicles that previously used Dextron III". It says right on the jug that it has excellent anti-shudder properties and a few other advantages. Normally I would say this is BS, and discount this, however, I've seen it in action: A few years ago on my 89 GMC pickup (700 R4 tranny) I replaced the filter and put in new Valvoline ATF. Not too long afterwards the tranny started acting up. The tranny would lurch, not shift into OD or shift in/out of OD, it was terrible. The truck has fairly high miles so I just figured it was giving up the ghost and planned to pull it out and get it rebuilt. BUT, I read one post on the internet that suggested that Penzoil ATF had better friction properties and has cleared up some tranny issues, and decided I didn't have a lot to lose. I did it (left same filter) and after about 25 miles or so operation returned to normal. That was about 8 years ago. I don't drive the truck very much, but just saying that it worked for me and I would consider it.

When I replace the tranny fluid I pull one of the tranny cooling lines (when they're accessable) and run them into a bucket. I overfill the tranny by about a quart or so and have my wife start the vehicle while I stand in front and watch the fluid that comes out of the hose. What it does is pump out the fluid from the torque converter (which you can't normally get out) and interrupts the fluid's path back to the tranny pan. Once the fluid turns clear red I know I've pumped out all the old fluid and signal my wife to shut the car down immediately. Everything happens quick and it only takes about 15 seconds. Then I top off the fluid like normal. That's how you get ALL the fluid out.

I know there are some who claim that you need to gradually change the fluid, but I don't know where that comes from (actually I do: people who have transmissions with 250k miles on them who claim the trans crapped out after they changed the fluid). I've rebuilt several transmissions. If you read the GM literature, their engineers basically say that replacing the fluid with new is always better than not. All the auto trannys I've looked inside didn't have a lot of crap to loosen up and clog things up. Ok, now I've started a firestorm and all the "you can't do that!" owners can spare the attacks.

Anyway, try using Penzoil and see if that does the trick. There are also anti-shudder additives you can buy and you could try them to your existing fluid first (easier to do) and see if that helps. Good luck.

 

I don't think this section will ever achieve "firestorm" status, seems it's getting little use these days, far less than ever before..........

I had a buddy who did the fluid change the exact same way, no firestorm here. I've done it too. You can pop a really small hole in the converter and let it drain and then use a pop rivet with seal to close up.

If anyone cares the ZF 4HP22 was used in the Rover P6B car and BMW used them in the E34's. Lots of care and feeding info on the interweb including surgery pics during rebuilds.

 

There are also no specific fluid recommendations from BMW for the ZF 4HP22 or 4HP24 trans. Just regular old Dex III. I'm a real big fan of this Mag1 juice so far.