canyncarvr
Well-Known Member
I looked briefly...didn't see this specific issue noted. It's got to be out there, I saying I didn't see it. Humor me.
I recently replaced the lube in my 8-3/4 for no particular reason...just seemed a reasonable maintenance choice after years (very few miles) of use. I used a bottle of 'additive' I got from O'Smiley's.
Results after a few drives? Noise. LOTS of noise. Gear-clunking, rocks-in-a-blender grinding, noise. ...and jerking around. All on turns. Slight turns made more racket than hard turns.
I put in a bottle of 'Genuine Mopar Fluid 4318060AB Limited Slip Additive', went for a warm-up drive.
Noise: Gone. Jerking around: Gone.
Point is: Not all 'additives' are the same (gee...really?). I don't recall the brand name I got from O's. It did NOT list 'Mopar' as a specific gear it fit.
The Mopar additive is readily available from Big River. It is less in cost than some others.
I've read (IIRC) a Doc Diff recommendation of Ford's fluid. I am not saying anything about that type/brand; have never used it.
It's easy to think your diff gears are falling apart, or grinding themselves into grey, glittery paste...and you might be WAY off in that thinkage.
The recommended quantity to use (commonly said to end up being 3-5%) is a bit less of the 4oz. bottle size into the 8-3/4 . I put in the entire bottle...minus a few dribbles I din't see coming over the top of the funnel I used. Chances of a 6.25% (four oz. in 64oz.) hurting something doesn't concern me. Keep in mind that unless you are filling a dry/rebuilt/new-install punkin', if you are only replacing the fluid with a vacuum/suck job, you're not going to get 4.4 pints into the thing anyway. The 4.4 pint number is from my Motor book.
It's been a LONG time since I had a clutch-style Sure Grip in this car. I'm 99.5% sure it's a spring-n-cone. Yes. I've read that the latter is much less susceptible to additive type/quality issues. This result is not from a double-blind placebo test of 100's of 8-3/4s. Just mine.
That IS what counts in The World of Science, right? Anecdotal proof, quantity: 1.
I did read an old post situation that may well have benefited from the use of Mopar fluid. That thread ended with no stated resolution posted by the OP. Suggestions of 'take it apart and check it out' were a bit drastic. Maybe not 'wrong', but misdirected. I'd say $10 for a bit of $320/qt. fluid that resolves a noise issue makes better sense. Heck, at that price level, even an adjustable PCV is reasonable!
To be sure: This is NOT about an 8-3/4 that's been used for years, and has developed a bad 'winding' noise.
There's an easter egg for 'ya. ...probably only funny in my own mind. ;)
I recently replaced the lube in my 8-3/4 for no particular reason...just seemed a reasonable maintenance choice after years (very few miles) of use. I used a bottle of 'additive' I got from O'Smiley's.
Results after a few drives? Noise. LOTS of noise. Gear-clunking, rocks-in-a-blender grinding, noise. ...and jerking around. All on turns. Slight turns made more racket than hard turns.
I put in a bottle of 'Genuine Mopar Fluid 4318060AB Limited Slip Additive', went for a warm-up drive.
Noise: Gone. Jerking around: Gone.
Point is: Not all 'additives' are the same (gee...really?). I don't recall the brand name I got from O's. It did NOT list 'Mopar' as a specific gear it fit.
The Mopar additive is readily available from Big River. It is less in cost than some others.
I've read (IIRC) a Doc Diff recommendation of Ford's fluid. I am not saying anything about that type/brand; have never used it.
It's easy to think your diff gears are falling apart, or grinding themselves into grey, glittery paste...and you might be WAY off in that thinkage.
The recommended quantity to use (commonly said to end up being 3-5%) is a bit less of the 4oz. bottle size into the 8-3/4 . I put in the entire bottle...minus a few dribbles I din't see coming over the top of the funnel I used. Chances of a 6.25% (four oz. in 64oz.) hurting something doesn't concern me. Keep in mind that unless you are filling a dry/rebuilt/new-install punkin', if you are only replacing the fluid with a vacuum/suck job, you're not going to get 4.4 pints into the thing anyway. The 4.4 pint number is from my Motor book.
It's been a LONG time since I had a clutch-style Sure Grip in this car. I'm 99.5% sure it's a spring-n-cone. Yes. I've read that the latter is much less susceptible to additive type/quality issues. This result is not from a double-blind placebo test of 100's of 8-3/4s. Just mine.
That IS what counts in The World of Science, right? Anecdotal proof, quantity: 1.
I did read an old post situation that may well have benefited from the use of Mopar fluid. That thread ended with no stated resolution posted by the OP. Suggestions of 'take it apart and check it out' were a bit drastic. Maybe not 'wrong', but misdirected. I'd say $10 for a bit of $320/qt. fluid that resolves a noise issue makes better sense. Heck, at that price level, even an adjustable PCV is reasonable!
To be sure: This is NOT about an 8-3/4 that's been used for years, and has developed a bad 'winding' noise.
There's an easter egg for 'ya. ...probably only funny in my own mind. ;)
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