Transmission service at 80k?
It's always good to change the fluid. What you need to consider is how you change it. You can just drain it, or you can power flush it with a machine (the way some dealers do it).
I'd drain the fluid immediately, then change again in a few thousand miles and stick to the schedule after that.
I would not even entertain the thought of a power flush at 80 000 miles.
Call around for prices.
The danger of changing the fluid on neglected transmissions/gearboxes/differentials/engines/etc. lies in the fresh fluid and additives dislodging large pieces of gunk that start flowing around and do damage.
When you just drain the fluid, you're not applying pressure to the gunk that's collected inside. Particles do get dislodged by the fresh fluid, but generally at a slow enough rate as to not cause damage and most of them get caught in the filter anyway.
When you do a power flush, fluid is injected by a machine through the transmission at high pressure, hence the name "power flush". It washes away close to all gunk buildups and flushes them right out. If you do power flushes religiously at every service, there won't ever be enough junk to cause trouble.
If, as is your case, you don't know the maintenance history, it's very risky to perform a power flush. There could simply be too much filth inside. A regular drain, however, does not pose a danger and is all but mandatory.
Many mechanics will be reluctant to work on heavily neglected components, because there's always the possibility of something failing then and there which means they'll have to eat the bill. If you do decide to go with the dealer, be very specific that they shall not attempt a power flush.
The pan should be removed & cleaned & the filter changed.
All the fluid should be removed ie the torque convertor drained via a drain plug or flushed as old fluid will oxidise the new.
In my opinion it is an old wives tale to not change trans fluid on a neglected auto.To let the transmission oil deteriorate further & collect more contaminants is putting your head in the sand.
In any case 80,000 miles is not completely neglected .
You should receive advice from a few experts who do this maintenance every day & see what they recommend.
Good luck & let us know how you go.
Last edited by Carsy; Dec 10, 2016 at 03:00 PM.
Last edited by dennish; Dec 10, 2016 at 07:20 PM.
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I changed my ATM fluid today.


It's always good to change the fluid. What you need to consider is how you change it. You can just drain it, or you can power flush it with a machine (the way some dealers do it).
I'd drain the fluid immediately, then change again in a few thousand miles and stick to the schedule after that.
I would not even entertain the thought of a power flush at 80 000 miles.
only good thing about a flush is no point in which it tranny is starved of ATF.


