Need opinion on my trans. fluid color

[Chance27]

I'm planning on servicing my transmission and wanted to know what others though about my plans. I bought my '05 Trailblazer LT EXT with 109K miles on it and I have no idea what the transmission service history is before that. I have not done any work in it myself since buying it and it's now at ~177K miles.

The color of the fluid looks darker than it should based on my research, would everyone agree that it needs changed?

So with that said, I'm planning on doing a pan drop (and replace with one that has a drain plug), filter change, and then refill with newer stuff (dextron VI), roughly 4 quarts.
Got a few questions though:

• After the initial drop and re-fill, how often should I be draining and filling back up until I reach mostly new fluid? Should I also change out the filter one last time to get rid of any gunk that was loosened?
• There was a thread on this subject that I now can't find, but someone commented that I can reuse the old metal core gasket for the pan, is this true?
• Lastly I'd like to know how common/normal it is for these trucks transmissions to sort of hang up on a specific gear when accelerating, specifically accelerating from 0mph like at a stoplight. It doesn't always happen, sometimes the shift is smooth, but other times it hangs for a second before there's a small jolt when it does shift. I'll also add that I'm aware fluid changes won't help me with this issue.

 

[Mooseman]

Yeah, you're overdue. I would do a fluid exchange to get all this old fluid out. It's easier than what you're planning to do (multiple pan drops).

Post in thread 'Transmission Fluid Quantity'

Jun 10, 2015

I can't see why not. May03LT has his own thread with links to all his videos but posting it here is a good idea regardless.

Heck, since he mentioned my name in the video, I'll post it myself! I feel like a star!

• Mooseman

• 

I don't think it's common for shift hangs but a Fluid change just might help it. We've seen seemingly dead trannys come back after getting fresh fluid and a filter as a clogged filter can give lower pressures.

If you have the rubber/metal gasket, it can be reused unless it tears during removal, is dried out or is deformed. If it's original, being 20 years old, may be on the dry side.

 

[Brian K]

I do a drain and fill with a new Wix filter (58847) every 30K miles. Years ago I added a tranny drain (Dorman 65241 on Amazon - once you drill the hole, you have it made lol) to my pan and that makes a fluid change MUCH easier. The first time is a PITA because fluid dumps all over so carefully remove the bolts and leave 1 on to let it drop slowly and you can catch most of the old fluid in a bucket. Before you get started, crawl under the vehicle and measure the pan - there are 2 different pans - a short and a deep one. Measure yours and go to the parts store and they can tell you which is which (sorry I forget - there is a difference in the filter). I reuse my pan gasket. Mine takes 4.7L of Dexron 6. At the same time it is a good idea to drain and fill your transfer case - 2 liters of GM Autotrak II. Easy to do too. Get an oil pump for that (and take the fill plug out first so you know you can re-fill it. And now that you're getting these done - change the 2 diff's while you're at it! I do all of this every 30K miles.

 

[Mooseman]

S

Thread 'trans pan-deep or not?'

Mar 14, 2018

how do I know if I have a deep transmission pan or not? I last changed fluid almost four years ago and due for another change....can't remember which filter I need.

• sunliner
• Replies: 3
• Forum: Drivetrain

 

[Chance27]

Thanks for the replies, sounds like it'll be easy.