Automatic transmission shifting problem

[danewilson77]

Right. Flushing (process under pressure) is sometimes detrimental as compared to draining (gravity).

[az3579]

Gotcha. Didn't realize flushing involved pressure. If anything, I thought pressure would be more effective, but now knowing that flushing involves pressure lets me see how that would be a problem with these auto's. Thanks guys.

[danewilson77]

Found this as well.

A power flush isn't a good idea as it can break loose crud in the transmission and plug up valves. A much better approach is a couple of drain/refills as they don't shock the system. You'll get about 2/3 of the fluid out on a drain where the pan is dropped, which should be done on at least the first drain/refill along with a filter change. So if you do a fluid & filter change and then do at least one more simple drain and refill after a few hundred miles you'll get almost all of the old fluid out.

It would be best to do a fluid change at about every 50k, but certainly by 100k. It is important to use the right fluid. Some BMW transmissions use Dexron and others use a special Esso fluid. Until recently the special Esso fluid had no substitutes, but Amsoil and Pentosin both have fluids now that can be substitued for the unobtanium (and pricey)
Esso.

Changing the fluid isn't a super simple procedure, but then it isn't rocket science either. Because there's no dipstick you can only check the level with the car level on jackstands or a lift and the fluid between 30 & 50C by checking for a small stream of fluid from the fill plug with the car running and in park (and A/C on). The Bentley manual has the procedure.

[WOLFN8TR]

What exactly is the difference between an oil change and a flush? I thought they were pretty much one in the same?

Sorry for the late reply, the pros beat me to it.

[tayyib330i]

alright so went to the dealership and they want 45$ for a liter of ATF2, and i read im gunna need like 10x that . so what have you guys done to get around this? ive been looking up and people have used mercon, Esso LT 71141, Redline D4 ATF etc. so which is the best for the buck. ill have to order the pan gasket and filter, so i guess i wont be driving for a good 2-3 weeeks..

guy at the dealership told me to just go my friends shop n just check if the fluid needs to be topped off cuz "its lifetime" hahaha but i dont think any fluid can last a life time.

[danewilson77]

I use Redline. It's done a good job.

No flame suit required!

[tayyib330i]

thanks Dane, thanks for ur quick responses! i owe you! ordering this complete kit from ecs http://www.ecstuning.com/BMW-E46-330...ion/ES2523867/

is there anything else you think would be causing this to happen the gears?! should i just order and install the intake camshaft position sensor too just in case?

[danewilson77]

Make sure you know what sticker you have on your tranny.

The friendliest forum on the planet.

[tayyib330i]

okk ill get under and check. but guy at bmw wrote this on a piece of paper, ATF 2 A5s 325z, thats the zf tranny right?!

[Dave1027]

I'm running Valvoline Dexron 6 with the GM 390 steptronic. Works perfect.