Frequency of fluid changes??? Trans and Diff
Thread Starter
Instructor
Joined: May 2006
Posts: 238
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From: Chicago IL 2002 Quicksilver Z06
Frequency of fluid changes??? Trans and Diff
My 2002 Z06 had ALL fluids changed six years ago and I have only put 15,000 miles on it since then. How often are you changing manual transmission fluid and differential fluid? I only drive the car for fun during the warm summer/fall months.
Burning Brakes
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From: NW Burbs of Chi-Town
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How many miles when you changed them the 1st time?
How did the drained fluid look?
Did you install magnetic drain plugs?
Most likely fine. If you can change the fluid yourself and dispose of the fluid responsibly, there is nothing wrong with changing it more frequently.
I got mine with 42,500 miles on it March of 2022. Its a 1998 Coupe with no records of MM6 trans fluid or diff/gear lube changed. I changed it after I drove it home from Montana. There was a little sparkly stuff (Normal) and was really dirty. I drove it a year and changed it again after fixing a leaky butt axle seal, decided to dump the trans fluid while I had it in the air. I keep fluids in stock in my garage for just such occasions (buy it on sale and have it on hand). Both trans and diff looked much better and magnets I installed pretty clean. I've since added significant power with upgraded Heads/cam/headers and will change it one more time in the spring. This is so far 17500-18000 miles in the 23 months I've owned the car. I tend to beat the snot out of it around town and run it at relatively high speeds on the highway. The fluids are cheap in the overall scheme of things.
How did the drained fluid look?
Did you install magnetic drain plugs?
Most likely fine. If you can change the fluid yourself and dispose of the fluid responsibly, there is nothing wrong with changing it more frequently.
I got mine with 42,500 miles on it March of 2022. Its a 1998 Coupe with no records of MM6 trans fluid or diff/gear lube changed. I changed it after I drove it home from Montana. There was a little sparkly stuff (Normal) and was really dirty. I drove it a year and changed it again after fixing a leaky butt axle seal, decided to dump the trans fluid while I had it in the air. I keep fluids in stock in my garage for just such occasions (buy it on sale and have it on hand). Both trans and diff looked much better and magnets I installed pretty clean. I've since added significant power with upgraded Heads/cam/headers and will change it one more time in the spring. This is so far 17500-18000 miles in the 23 months I've owned the car. I tend to beat the snot out of it around town and run it at relatively high speeds on the highway. The fluids are cheap in the overall scheme of things.
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I would say every 3-years or 25,000 miles (my opinion), whichever comes first. Fluids are cheap, the components aren't in comparison.
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Those fluid changes should be covered in your scheduled maintenance listing in the owner’s manual. But as mentioned, doesn’t hurt to be change things more often.
Team Owner
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From: Western NY
I agree. My C-5 has only 30,000 miles on it, and it's approaching 23 years of age. In my car, those fluids have been changed at least twice, possibly 3 times (old age memory issues!), which equates to about every 8 or 12,000 miles, but as you say, gear oil is inexpensive, in comparison to what those components cost.
Thread Starter
Instructor
Joined: May 2006
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From: Chicago IL 2002 Quicksilver Z06
Thanks for the recommendations. The car had 37,000 miles on it when I bought it in 2017 and now is has about 52,000. I only drive it about 2000 miles per year and definitely don't beat on it. The fluids are easy enough to change. I have read through my service manual to check the fluid change intervals too. It is surprising that GM states the manual transmission fluid doesn't need to be changed. It is cheap insurance to change the trans fluid.
Pro
Joined: Sep 2018
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From: Nova Scotia Canada
My entire career has revolved around preventative maintenance. I do track my car and for the minimal cost diff and trans get done at the start of every season. Is it necessary? Not likely. Has it been beneficial? Definitely as I've caught issues in the past before they got worse. It also helps me sleep at night.
I'd focus more on your clutch fluid. Seriously. Do this often. It'll save you a lot of grief and expense in the long run. Brake fluid is a great idea while you're at it.
I'd focus more on your clutch fluid. Seriously. Do this often. It'll save you a lot of grief and expense in the long run. Brake fluid is a great idea while you're at it.
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I was looking this up this morning... funny to see this thread. Thinking I will change my diff fluid here in the next couple weeks. It's been ~3 years. Not many miles in that time, but I am driving the car more now that I've moved.
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Well documented and durable A4 here. Changed fluid and filter at 100,000 miles. Changed diff fluid then, too. At 142,000 miles now, with the 600hp LS7 still beating on the original A4, and diff. Just get in, start, select OD, and go like Hell!!! No issues.....Yet!
Pro
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It's consistently astonishing that it isn't recommended, with both manual C5 vehicles I've owned, changing the fluid after a certain mileage has consistently yielded positive outcomes. The improvement is especially noticeable in the color and condition of the replaced fluid, making the process a valuable form of preventative maintenance.
If GM observed similar problems while torture testing their transmissions, it would make sense that they would want to seal the transmission (no dipstick) and discourage any transmission maintenance. Of course this is a strategy to minimize warranty costs, not a strategy to maximize the life you your drivetrain.
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Some transmissions are finicky. If you miss a scheduled automatic transmission fluid change and then wait too long, you run the risk of inducing problems with a fluid change. I have more experience with ZF transmissions and I saw several older models that lost all forward gears as a result of simply changing the transmission fluid and filter. Apparently bits of debris break loose and lodge themselves where bits of debris have no business being lodged.
If GM observed similar problems while torture testing their transmissions, it would make sense that they would want to seal the transmission (no dipstick) and discourage any transmission maintenance. Of course this is a strategy to minimize warranty costs, not a strategy to maximize the life you your drivetrain.
If GM observed similar problems while torture testing their transmissions, it would make sense that they would want to seal the transmission (no dipstick) and discourage any transmission maintenance. Of course this is a strategy to minimize warranty costs, not a strategy to maximize the life you your drivetrain.
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I see no issues manually changing the 4L60E fluid and filter correctly. The problems I've heard and read about are always about having a higher mileage trans flushed with a machine. I don't see how draining the fluid by dropping the pan, changing the filter, and refilling with new fluid could hurt anything. You're actually only changing about 1/2 to 2/3 of the fluid anyway.....
Pro
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I see no issues manually changing the 4L60E fluid and filter correctly. The problems I've heard and read about are always about having a higher mileage trans flushed with a machine. I don't see how draining the fluid by dropping the pan, changing the filter, and refilling with new fluid could hurt anything. You're actually only changing about 1/2 to 2/3 of the fluid anyway.....
If I bought a high mileage car with an unknown service history, I think that I would be inclined to do a series of "drain and refills of only one quart of ATF at a time" and stretch these mini-services out over a couple of months, before I dropped the pan to change the filter. Sure, this would be a PIA, but how much of a PIA would it be to have the transmission rebuilt?
But, that's me. Obviously, YMMV!
