Hello i have a daily driver 2008 m6 that hit 52k miles and i recently did the ranger method for the clutch and they say it takes about 4 attempts to get clear fluid which is correct but when i took it for a test drive around the town and got back it had black fluid so i did another 3 or 4 attempts and it stayed clear on Sunday. Took it for a longer drive and got back and it was not as black but still dark. Is this normal?


Second question,


The rear end is whining a little and i probably need to change out the fluid, i have never owned a manual car before, so for maintenance im new to all this. The transmission fluid is in the back correct? Does it also have a differential in the back that have drain and fill plugs? What do you recommend for the transmission fluid if autozone or O'reilys does not carry the ACDelco 88861800: ACDelco Manual Transmission Fluid?

 

Its going to take you about 5 tank fluid swaps in so many weeks to get the fluid clear and stay clear for a while. So at this point, don't need to do the pedal pumps any more (driving will do that) but do swap it out in the reserve tanke every few days of driving for the next few weeks. Once it starts staying clear, then it just a mater of every few months of changing the fluid out in the tank instead.

As for Diff and Trans fluids (two different units), yes on the A/C Delco correct fluids, and you have both the trans and the diff in the back of the drive line.

The diff gets drained, then filled back up to the fill port level with the car level, while on the trans, would help to know if you have a cooler or not (is the trans a M6 without cooler or Mz6 like in the Z51 option car with cooler).

Hence it the same thing with filling the fluid level back up the filler port level on the trans, but on the trans will cooler, you need to run the trans on a lift so it fills the cooler and lines back up before you call it filled to the filler line.

Truth is, with only 50k on the car, would just get under the car with it level to pull the filler plugs, check the fluid levels and the condition of the fluids to start with (did you finger in the fluid through the fill ports).

The trans fluid should be fine, while if the car has been driven hard and the diff fluid is dirty with a lot of clutch dust (from the LSD clutch packs that have worn), then it may warrant a diff fluid change alone.

Here is the fluid for the diff,


Here is the fluid for the trans,


To add the fill port are upwards, so you will need a pump and tubing to pump the fluid into the fill ports from the bottle of lube. And again, make sure the car is level in the air so you are topping the trans and diff off correctly.

 

man thank you for all that! So is it not really necessary to change the manual fluid? I am wondering what the whine is and i know its coming from the rear end, i guess differential?

 

oh and my c6 isnt the z51 no cooler lines.

 

Whine is hard one to tell you where the noise is coming from over the internet, and could be a problem with the torque tube couplings going out, and maybe what you are hearing is the disc on the drive shaft just rubbing on the inside of the torque tube,

Or could one of the bearing in the diff is giving up the ghost isntead.

So at least start with checking the level visual inspect of the fluid conditions to start with.

 

Alright i will check that this weekend. I need to change the oil and do some other little things to it. So ever since doing the Ranger Method my clutch fluid is slowly turning more clear which is good, but I have another question now.


My clutch when i push it in feels sluggish/ a little sticky as i push it in and isn't a smooth push anymore. What could cause that issue?

 

You need to get under the dash and re-grease all the pedal contact points of the actual pedal system itself, as well as lube the end points of the assists spring and it's loop area to the pedal bracket as well.



Note, nylon cup #11 and maybe missing or worn threw for the spring loop.


While your dug in like a tick under the dash (playing contortionist) pulling the clutch pedal assembly to work on it back at the bench, not a bad time to do the brake pedal as well. Both have inner sleeve parts that run on a through bolts, and greasing all the parts does wonders.

Once you remove the retainer pin that holds the clutch master cylinder shaft to the clutch pedal stud, you can remove the entire clutch pedal assembly to pull it out via is bottom and side bolts, which give you room to pull the through bolt for the brake pedal a well.

 

Thanks for your advice man. I am going to change the fluid this weekend.

 

Hey Dano or anyone else, if im going to change the tranny fluid. what is something i can pick up at autozone or o'Reillys that will work with the base c6 model?

 

If it’s a Tremec TR6060 transmission, you can use Mobil 1 synthetic ATF (yes, for a manual tranny). Actually what was recommended to me by customer service at Tremec last winter when I changed the fluid in my 2005 C6

 

so did you figure out why/where your whining sound was coming from?