Ok, this is a question and poll for all the guys running automatic transmissions: Transmission service includes fluid change, cleaning strainer and adjusting bands.
My vote is every two years or 24000 miles - whichever comes first. I am wondering how often most people service their C4s and AODs.
Guess i'm out. I have 15 or so years and about 200-300 miles on mine. What ever you recommend when I do get it on the road again
I dont know which to choose. before i overhauled the engine it was like every two years not keeping track of mileage. then i didnt drive it as often so i went to every three years. then i bought a new trans just because i figured over 200k miles on it behind a stronger motor was going to get me sooner or later. then i put in the P.A. 500 horse one and had to take the pan off once a year to fix leaks, thus a fluid and filter change yearly with very little miles on the car, as i am trying to cut back on driving it... just a good thing it snows here or i suspect i would fail and drive it more...
I always thought that if you have an old tranny and don't know what condition it's in then better not to change the fluid. But to keep a tranny for a long time you should change the oil every 15,000 miles.
The C4 gets fresh fluid when the mod valve goes out. So... every 5 years or so Back when I had a couple AODs in F150s, the fluid got changed every couple of years, and Id drop the pan and replace the filter every other time. Sometimes sooner if I burnt the fluid towing, etc What's the SOP when using a good synthetic lube? Go longer? How much longer?
My vehicles get the trans, diff and transfer case every year. My Jeep gets trans fluid 2 or 3 times a year since it has a drain plug and the fluid is free. Takes 2 minutes to drop it with the engine oil. I love my AW4!! In 19 years at the dealer I have yet to see one fail. My 2002 300M gets trans and diff once a year. The Mav. will get trans. service each season. Keep in mind I dont pay for the services so the intervals are more than necessary. I suggest every 2 years for trans service unless it sees heavy loads then every year. Our intervals up here are more frequent due to our climate. Our fluids have to work from -30 up to Summer temps of +30C. Our cars take a beating up here. Very cool poll. We discuss this a lot at work. Our +4 fluid is a long life and some trans are fill for life. (so they say) We still service them every 2-3 years.
i just drained my c4 at 3500 miles, because im changing the conveter. i have seen a quite a few fail when there burnt fluid is drained out. my question to paul is if the fluid is burnt or brown should it be serviced or not?
Guys in the trade argue that one all the time. Personally I have seen quite a few fail when burnt fluid is changed. Likely would have failed soon anyhow. Other techs call it an old wives tail. Depends who you ask I guess. Do I change burnt fluid at work. Nope. Reason being that if I open that trans and service it then it blows up I'm on the hook. Cant trust a service writer to explain it to the customer properly. What would you do with a burnt fluid Paul??
Burnt fluid carries with it carbon and a total lack of lubrication and cooling ability. The faster you get it out of the transmission the better off the transmission is. If the fluid is burnt the transmission is already in need of a rebuild. The fluid doesn't burn until it gets over 280F. At 250F the clutch and band linings are already gone unless you are running Kevlar and carbon. If you are running exotic frictions then you should be running Mercon V and it doesn't burn until 350F - at which point the steel plates have warped and you need a rebuild. So, no, you shouldn't replace the fluid - you should have the transmission rebuilt, but if you have to drive it then yes get the burnt fluid out of it.
