[r0bert]

Just did a transmission fluid change on my GA6L45R with 163,000 miles on it.

I changed fluid because a rough vibration coming from torque converter.

If (crossing my fingers it won't happen) putting new fluid would to mess up the transmission at those miles, when would you think it would start messing up?

Immediately?
Few hundred miles?
Few thousand?
Who the hell would know that?

Just curious.

Thanks!

[AoS810]

I'm gonna go with option #4!

I did a drain and fill only at 101k miles, and a drain, filter and fill at 107k and I haven't noticed anything odd with transmission behavior after both times (I'm at 111k now). Yours at 163k is pretty overdue but as long as you added the correct amount at the right temperature my thoughts are new fluid is always better than old fluid.

[mecheng77]

Do the trans adaptation reset

[tlow98]

Mostly positive results posted by changing fluid.

[ChuckThomas]

First off, did you find any metal in your transmission pan. If not, you pretty much have nothing to worry about as long as none of your gaskets are leaking fluid. One thing to look out for regarding the torque converter is SURFACE RUST on the outside. If you ride with splash guard off or water gets in there, rust will start to form on the outside causing it to be loud and vibrant. I don't know if that's your case or not but KEY thing is metal in pan??? You should be ok if no metal at all was found in pan. And don't believe the "lifetime" fluid, it should read "100,000 Mile warranty lifetime"

[AWDBooSTIn90]

^x2

if the pan was clean, and you changed the filter/pan and fluid, and then did the Trans Adaptation that is needed when the fluid is changed, you should be fine. These Trans. are pretty solid. At this higher mileage, dont do any "Trans Flushes" or anything like that.

you could also do a Drain & Fill two more times. 1st time would be about 2-3k miles from now and the last drain/fill in 5-7k miles. Then change the fluid every 60k miles like everyone should be doing.
There's no such thing as "Lifetime Fluid,"... To me lifetime fluid is their excuse to not have to change the fluid under the maintenance plan. You could stretch 100k miles out of the stock fluid, but i recommend changing all the fluid every 60k miles!! (AT/MT, TC, Front Diff, Rear Diff).
Brake fluid is also commonly overlooked, that should be changed like the OBC says, about every 3 years. Same with performing a drain/fill for the coolant and other fluids like the P.S. fluid - i.e.(suck out old fluid from Reservoir and Re-Fill).

[CTinline-six]

You would know pretty soon if the new fluid damaged anything. I saw a transmission where the wrong fluid was put in it and was under filled by a shop and a few days later the trans shit the bed.

Every time I've changed the trans fluid in any vehicle, Jeep, Honda, Ford, BMW, Chevy, the shifting improved. The best way is to do drain and fills with a bit of driving in between to slowly refresh the fluid. I've done this on transmissions with over 100k miles with no issues. Power flushing is what you want to stay away from.

[Riick]

The GA6L45R service schedule is a fluid drain and filter every 30k miles. How in god's name it lasted 165k on the original filter/fluid is a miracle. You should buy a lottery ticket.

[CTinline-six]

Originally Posted by Riick

The GA6L45R service schedule is a fluid drain and filter every 30k miles. How in god's name it lasted 165k on the original filter/fluid is a miracle. You should buy a lottery ticket.

Not really. Not saying it is a good thing, but you would be surprised how many vehicles go 200k on their original trans fluid. In fact I've seen more failures of rear differentials where the fluid leaks out than failed transmissions with original fluid. Shifts might be rough as hell or slip, but they keep going.

With that said, there are many transmissions where changing the fluid WILL increase the life of it substantially.

[Riick]

The 6L45R will last forever if you follow the correct service and use the correct fluid released from the company who makes it. Any decent attorney can win in claim's court for BMW's false advertising about it being "lifetime".

[tlow98]

Originally Posted by Riick

The GA6L45R service schedule is a fluid drain and filter every 30k miles. How in god's name it lasted 165k on the original filter/fluid is a miracle. You should buy a lottery ticket.

Where is this service schedule spelled out?

[CTinline-six]

Originally Posted by tlow98

Where is this service schedule spelled out?

I believe this is a recommendation by GM, the manufacturer of the transmission for other models that this transmission is used in. I believe a few Cadillacs have it?

I could understand BMW wanting to market lifetime fluid for "ease of maintenance" for potential buyers, but when dealers turn people away who actually want to change their fluid that doesn't make any sense.

[MysticRob]

Originally Posted by r0bert

If (crossing my fingers it won't happen) putting new fluid would to mess up the transmission at those miles, when would you think it would start messing up?

Immediately?
Few hundred miles?
Few thousand?
Who the hell would know that?

I'm betting on next Tuesday at 4:37pm local time.

Seriously, I've yet to hear anything like this occurring on newer transmissions, but recall stories of the older 60s trannys having issues if a 'proper fluid' change suddenly led to problems. The problem wasn't the new 'proper fluid', it was an underlying issue the old fluid was masking because of whatever properties it accrued over those many miles.

Examples I heard would be so much worn clutch-pack material free-floating in the old fluid that that old fluid essentially became the only thing with enough friction to allow gear engagement. As soon as new fluid was used it caused slipping. Again though, no first hand knowledge, just what was explained to me by 40+ year dealership mechanic Dad and his friends.