M/T Transmission Fluid Change Question

[Marukai]

I'm thinking about doing my tranny fluid myself since I do my oil myself. I change my oil by driving my car onto ramps. I'm thinking about changing my fluid on ramps but have a few questions.

Once I get the bolt off and the fluid drains can I start the car and roll it down the ramps so that the fluid can continue to drain and then drive it back up without the fluid in it to refill?

I know this maybe a silly question but the people on Subaru forums have done this method on the rear differential.

Isn't the transmission pretty much the same as the rear differential in that both contain gears with teeth and the same gear oil?

 

[Captain_Klink]

you'll make a mess on your driveway.

 

[Marukai]

But will this work? I don't see any harm since I'm only driving the car up small ramps once the tranny is empty to reinstall the drain plug and refill

 

[hate2work]

Tell us again the purpose of doing this? Is it to get more oil out? If you need the car level to drain properly, I would simply jack up the back of the car while the front was on the ramps. When it stops draining, lower the rear and go from there.

 

[Marukai]

Originally Posted By: hate2work


Tell us again the purpose of doing this? Is it to get more oil out? If you need the car level to drain properly, I would simply jack up the back of the car while the front was on the ramps. When it stops draining, lower the rear and go from there.

It's to drain the oil fully. The oil will only drain partially if I have it on ramps. If I roll it down the ramps so that it's level the rest of the oil will drain out. I don't have a jack. I've been doing my oil and rear differential oil with just ramps. I was hoping to continue this economically.

 

[Texan4Life]

why not just leave the engine off and put it in neutral and roll it off the ramps?

 

[Marukai]

Originally Posted By: Texan4Life
why not just leave the engine off and put it in neutral and roll it off the ramps?


If I do that I will still have to start the car and get it back onto the ramps to put the drain bolt back in.

 

[Kiwi_ME]

I don't see a problem.

 

[mechtech2]

Before you start, make sure your fill bolt can come off!

 

[Marukai]

Originally Posted By: mechtech2
Before you start, make sure your fill bolt can come off!

What do you mean? I would have the filler bolt completely out, so that all oil could drain.

 

[Marukai]

Can anyone else also confirm that it's OK to start the car without any fluid in the tranny? Does the tranny move at all when the car is in neutral?

 

[Propflux01]

Originally Posted By: Marukai
Originally Posted By: mechtech2
Before you start, make sure your fill bolt can come off!

What do you mean? I would have the filler bolt completely out, so that all oil could drain.



Most trannies have a vent system, so taking off the filler bolt to 'drain it all out' is unnecessary. ALot of folk will pull the drain plug, only to find out the filler plug is stuck tight and may take some really hammering to get it off to fill it. better to find out before you drain it and can't drive it to get that special 4 foot breaker bar!

 

[Mr_Joe]

Once you drain a good amount of tranny fluid out there is a good chance the car will not be able to drive back up the ramps. I'd do it all without any driving, shouldn't be to hard. Trannies don't work well when low on fluid.

 

[scurvy]

Why use ramps if you want to get it 'level' to drain 'properly'?

Either use a jack & stands to put it up initially, then lower & back up; or put the front end up on ramps, lift up the rear of the car with a floor jack to let it drain 'level'.

Do not drive or roll the car without fluid in the transmission - EVER!

 

[mechtech2]

Sorry, what I meant was:

"Before you start, make sure your fill bolt can come off!"

 

[scurvy]

Originally Posted By: mechtech2
"Before you start, make sure your fill bolt can come off!"
Excellent point - always take off the fill plug before you touch the drain!

 

[johnd]

Quote:
Once you drain a good amount of tranny fluid out there is a good chance the car will not be able to drive back up the ramps. I'd do it all without any driving, shouldn't be to hard. Trannies don't work well when low on fluid.


Aren't we talking about a _Manual_ transmission? Should work if fluid in it or not-at least for a while.

 

[Kestas]

One summer I was a student engineer at Ford Manual Transmission. I remember the guys got a transmission back that was replaced under warranty. The factory forgot to fill the oil charge, and it ran 600 miles before it was turned in by the customer. Though they weren't happy about the factory goof, they remarked at how well the transmission could run on just mill oil!

 

[scurvy]

Originally Posted By: johnd
Aren't we talking about a _Manual_ transmission? Should work if fluid in it or not-at least for a while.
Sure, but why bother driving it at all if you don't need to? Use a floor jack to get the other end up in the air to make it level.

I don't disagree that it should be OK for a short distance but I certainly wouldn't drive my cars without transmission fluid in their manual transaxles.