Transmission servicing question (3 Viewers)

[SoCal818]

Ok, I’m posting here because I’m getting differing statements from friends. My 05 Sequoia has 235k on the odometer. I picked it up around 200k and have made a point of replacing damn near every fluid and wearable part. The only thing I’ve not done is service the transmission. It shifts well and it’s not presented any issues.

The question is this: I’m going to be towing a 5k trailer in August up 395 (Eastern Sierras of California so think hot weather with some tough elevation gains climbing into the mountains). Would it be wise to have a fluid swap (not a flush) or maybe even a drain n fill (3-quarts at a time sort of thing). Or do I dare leave it alone and not try to fix something that’s not broken? I’ve received comments across the spectrum on the issue. Putting it to this group for your input.

Thanks

 

[vtl]

Drain&fill a few times with some miles/days in between, so it has time to soak additives into frictions and relearn shifting.

 

[SoCal818]

Drain&fill a few times with some miles/days in between, so it has time to soak additives into frictions and relearn shifting.

Thanks. I like that approach. Would you recommend draining and replacing while everything is cold? (Eg: Crack fill plug, crack drain plug, drain, and replace with the same amount that drained). Or bring it all up to temp and do it per manual?

 

[vtl]

Thanks. I like that approach. Would you recommend draining and replacing while everything is cold? (Eg: Crack fill plug, crack drain plug, drain, and replace with the same amount that drained). Or bring it all up to temp and do it per manual?

Drain in a comfortable temps, don't get burns. If you leave it draining for a few hours, 1.5-2 more quarts may come out. Fill in as much as drained, don't bother with leveling the fluid. If you have OCD, can do that after the last drain&fill