XT5 dark trans fluid drained at 31k mi

Joined
Aug 10, 2004
Messages
1,508
Location
High in the Mountains of Central California
This is my Cadillac XT5 with a 9T50 transmission and a LSY 2.0L TGDI engine.

I bought it used when it had 21,500 miles on it, back in October of last year.

My plan has been to do drain and fills at approximately 30,000 mile intervals but the technician who did the drain and fill said that the fluid looked almost black. He can’t smell, so he couldn’t comment on that.

I am alarmed because both the previous owner and I are relatively gentle drivers, but I live near the top of a mountain and have to ascend steep grades on the interstate on a regular basis.

After this recent fluid change I switched the dash readout to transmission fluid temperature as I drove home and on the flat section of the highway it was 205F - 209F and then it went up to 216F on the steep 6% grade.

The ambient temperature range was 105F - 107F.

The shop used dealer-sourced DexVI.

I’m seriously considering doing another drain and fill after 5,000 miles and switching to Valvoline Restore and Protect ATF, doing a double dump to get closer to 100% fluid change.

From that point I’ll go 20,000 miles and see how the fluid has held up at that drain and fill. At that point I’ll decide what interval I should use going forward.

Thoughts, please!
 
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Just a couple thoughts.

The color doesn't always match the condition of the fluid. Some just get darker after heating up a few times.
You didn't actually see the oil? The tech may have fishermans disease (I once caught a fish this big!) or he may want you to think he just barely saved you from calamity. So many unknowns at this time.
 
Is there a transmission cooler in bottom of radiator like some vehicles? Are there cooler lines going from a hockey puck style back to tranny?

Quick search shows a towing package option that had other cooler options. Maybe you can add an aftermarket version in line or get factory stuff.
 
My original plan, when I bought the car at 21,500 miles, was to do a drain and fill at 30,000 miles, and then every 30,000 miles thereafter.

I came up with that plan because I had done research and found that this trans does not have a serviceable filter. The pan is vertical, so essentially nothing is held in it by gravity. It has a drain plug at the bottom, a fill port at the top, and a fluid level plug on the side. It's set up for doing drain and fills.

After hearing the tech describe the drained-out fluid, I decided to alter my original plan to 20,000 mile intervals. Then, I started to explore changing fluids entirely, which is when I decided to go to VRP ATF. When I switch to that, I want to do two drain/fills back-to-back to get the fluid in the trans closer to 100% VRP ATF. Then I was thinking of doing another short (20,000) interval with VRP ATF to see how that higher quality fluid does, and if it does well, then I'll go back to 30,000 mile intervals.

Is that close to what you guys are saying? I really appreciate all of your suggestions!
 
I like your plan. I would drop the pan for cleaning and to add some magnets but I think 2-3 drain & fills is a good start. R&P ATF is what I would use if it was available in Canada.
After reading your post I then looked into it more and found that Valvoline indeed recommends three back to back drain/fills at the start of using VRP ATF. I’m going to run the existing DexVI through this engine OCI and then switch to the VRP ATF at the same time I change the engine oil.
 
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