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I know this has been discussed before but I was hoping to get some thoughts on all the different recommendations. I just did my "break in" oil change at 1500 miles (cue off topic break-in need discussion!). I then left on a 3 day 1200 mile trip. Just got back. At about 1800 miles all of a sudden the rear end started whining louder than hell at light throttle. Drove me nuts for the entire trip. I want to change the rear end, transmission, clutch/brake, etc. as soon as possible to help with noise and the god awful shifting. Hell, I'll even change the windshield washer fluid if it helps performance! ;D

So, what fluids do I need to change, what are the latest recommendations, etc...?



#LS-378 - So many Porsche's, so little time....
I use Redline MTL in the tranny and Redline Lightweight Shockproof in the rear diff. That said, if you have noises like that coming from your rear end (Torsen ?) I would change no fluids yet and get it back for service.
Yes, I'm definitely gonna have it looked at before swapping fluids. However, I was gonna take new fluids into the dealer and have them swapped while they have it. I am using a Roush dealer as they seem to have a pretty good understanding for, and tolerance of, performance upgrades and the type of customer that buys Boss/Roush/Shelby type vehicles. Too many places I spoke with have the "Yeah, it's just another Mustang" attitude or, they are the kind of places that wanna blame tranny issues on CAIs. I had to find a local dealer because I drove over an hour to find my GHIG Boss.


Zaino, I put that $hit on everything
I notice a high pitch 'whine' from the rear axle when cruising in 6th gear on the highway. Tried to demonstrate the sound to the wife by taking the load off the axle by dropping it into neutral, getting back in gear, repeat. She couldn't hear it. Ugh.

Interestingly enough, I noticed this on the original drive shaft, and then after the swap to the aluminum shaft, the whine was still present but at a higher pitch/frequency. Still wondering if I will bother demonstrating this to the dealer will do any good. I never got a coupon for a free oil change or anything, so it's not like I have a reason to drive ~25 miles out of my way for a dealer service.

Regarding 'break-in' I am going to run the factory fill until just before I put it away for the winter in December, then I will dump the Motorcraft for Amsoil+Filter. Will send the original oil out for analysis and check the results. I haven't been burning any oil at all, been checking the dipstick on every fill up which is about every 200 miles.

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