Hello all,
I am ready to tackle the transmission fluid and filter change. I have read a lot of posts about this. Tell me if I have it right.
Drain the fluid, measuring how much comes out.
Remove the pan.
Make sure the surfaces are clean.
Install the new pan with the new bolts.
Refill with the same amount of fluid as you removed.
Drive it a while and then do a drain and fill x 2 or 3?

What am I missing?
2004 XK8

 

When I renew the fluid on a gearbox, I don't measure the 'waste-oil' so I can't comment on that procedure but if you remove the pan, replace the connector sleeve as a precaution.

You have to remove the level plug to fill the gearbox so why not just fill it correctly and watch the temp?

You cannot measure exactly how much fluid is in the pan/filter when you discard it so it will be a close guess as to the last little-bit but you can get close?

What if the level is incorrect when you measure the drained fluid? Is there some loss over the years and you now under-filled the gearbox?

Things to consider.

 

I did mine the way you are thinking and the biggest issue for me was getting the car level and high enough to work under. However I was considering doing a "flush" where a shop will just hook up to the cooler lines and replace the fluid without dropping the pan or replacing the filter. The claim is that it cleans out the "sludge" and replaces all the fluid with clean. Has anyone tried it?

 

If you are going to carefully measure and replace with the same amount (as I usually do on my cars), make sure before you start that the fluid is at the proper level, and that the fluid going in is at about the same temperature as the fluid coming out.

 

The potential risk with an ATF flush is that the process may drag long-settled debris up through the valve bodies, creating serious problems that you did not have before. I will stick with regular drain-and-fills....

 

This looks like as good as any place to put my hint to help getting as much transmission AND engine fluid out as possible by draining alone.

In my experience with cars in general I have found that the design of some pans will always NOT let all the fluid drain out. Take a strip of old cotton clothing (like T-shirts) and twist it into a wick then stuff one end into the drain opening, making sure that a goodly section is in where it should pick up the most fluid. The other end of the wick should be positioned over your catch device. Size of the wick before twisting should be 10 by 20 inches or so. Then retire for the day. If it is still dripping the next day, give it more time. When you finally remove the wick, give it a slow twisting motion to keep the twist so that you minimize the chance of the wick catching on anything internally.

John
Near Baltimore

 

This is just me. And this is if I trust/know the level is correct.

Drain the fluid. Drain it cold or close to cold or, so the fluid flows, get the car warm/hot, drain it, and let the fluid cool completely before measuring its level in bucket/pan...If you weigh the oil, of course don't worry about temp...

Change the pan. And yeah, pay a bit of attention (estimate/guess) to what's still in it upon removal.

Once the pan is buttoned back up, remove (carefully) the TOP trans cooler line off the radiator, at the front RH corner of engine bay, and PUMP the new fluid into the cooler return hose + a half quart. Done. Replace the small oring, nip up the hose to the rad (NOT too tight, it doesn't take a lot). And go for a drive.

I don't get under cars unless I have to anymore, especially for long periods while the damn thing is running. Nope. I'll get a lift some day.

 

You will NEVER drain the torque convertor (or other UN-DRAINABLE areas) with a static drain/fill so several 'sessions' will be required if you pursue this line of action.
6 or 7 liters is all that you will drain out of the 10 liters original fill.

Dynamic fluid replacement is an option if you understand the operation and have the equipment.

Both ways have merits.

 

Sorry ERROR >>>> LH front corner of engine bay