second time for metal flakes in the gear lube... why?

Posted By: 67dodge67

second time for metal flakes in the gear lube... why? - 08/16/09 12:32 AM

About two years back, the clutch packs became damaged and ended up leaving a ton of metal flakes in the gear lube (8 3/4, 742 carrier, locker). Initially, I had a shop set up the rear end and after it happened, I went to a different place to get it fixed. Back then, it had lasted a year, almost to the date. The car had only a dozen passes (67 Coronet, 470, 727, 3.91, MT radials) and I can't believe they have gone bad AGAIN.

The first shop I had it done at was probably not the best route to go, but as far as where I got it 'fixed', they DEFINITELY knew what they were doing. It has been a year AGAIN, almost to the date, and again about a dozen passes this year. I once again have metal flake in the gear lube and I'll bet a brand new Ben Franklin I know what it is.

Soooo... the question is this. I do not want this to happen again so what can be done to prevent it? Is there a way to 'beef' it up or install 'stronger' parts? I have no idea how to repair these and will have to take it to a different shop to get it fixed.

I thank you for your input. Dave

Posted By: dOoC

Re: second time for metal flakes in the gear lube... why? - 08/16/09 12:43 AM

You say a TON of flakes ? ... could be the bearings coming apart. Have you got a little donut magnet to put in there?

Posted By: 67dodge67

Re: second time for metal flakes in the gear lube... why? - 08/16/09 12:49 AM

forgot to include this, the green bearings are new and were packed/installed correctly. thanks.

Posted By: J_BODY

Re: second time for metal flakes in the gear lube... why? - 08/16/09 01:24 AM

running the mopar friction modifier?

Posted By: MR_P_BODY

Re: second time for metal flakes in the gear lube... why? - 08/16/09 02:03 AM

Why not put a spool in it

Posted By: 67dodge67

Re: second time for metal flakes in the gear lube... why? - 08/16/09 02:24 AM

Quote:

running the mopar friction modifier?

I did add a friction modifier, but not the mopar one. Does that make a difference? The name of it is Trans-X posi-trac limited slip gear oil additive. Sorry, but I'm new to this.

Thanks for your help. Dave

Posted By: 67dodge67

Re: second time for metal flakes in the gear lube... why? - 08/16/09 02:27 AM

Quote:

Why not put a spool in it

The car sees MAYBE a dozen trips to the strip in a year. It's basically a street car. From what I understand, a spool is not good for the street. Am I wrong?

Thanks for your reply. Dave

Posted By: MR_P_BODY

Re: second time for metal flakes in the gear lube... why? - 08/16/09 02:37 AM

Quote:

Quote:

Why not put a spool in it

The car sees MAYBE a dozen trips to the strip in a year. It's basically a street car. From what I understand, a spool is not good for the street. Am I wrong?

Thanks for your reply. Dave

I drove one on the street for a FEW years... cant take
corners quick other than that it was fine

Posted By: J_BODY

Re: second time for metal flakes in the gear lube... why? - 08/16/09 03:53 AM

Just wondered... Guess that's the only thing that came to mind as it sounds like you wiped out the clutches for the sure grip and not the pinion or side bearings. Did the rear ever feel "grabby" when making slow sharp turns? (parking lot manuevers)

Posted By: 67dodge67

Re: second time for metal flakes in the gear lube... why? - 08/16/09 04:13 AM

Quote:

Just wondered... Guess that's the only thing that came to mind as it sounds like you wiped out the clutches for the sure grip and not the pinion or side bearings. Did the rear ever feel "grabby" when making slow sharp turns? (parking lot manuevers)

It DEFINITELY does. When I make a sharp turn, like out of a gas station, I can tell it seems to 'grab' or 'bind up' and lose power. I also have heard a LOUD 'snap' when making a VERY sharp turn, but only after it has started up and I pull it out of my storage garage or the gas station which is just around the corner (2 minute drive). After it warms up, it goes away.

I have heard a VERY loud 'bang' which sounded as if the rear brakes were 'stuck' together and then seperated, as if they 'popped' open; as if they were rusted together due to sitting after a year or two.... or the emergency brake was stuck and it then popped free. That's the sound it makes....

Thanks.
Dave

Posted By: J_BODY

Re: second time for metal flakes in the gear lube... why? - 08/16/09 04:37 AM

Well that's how a sure grip feels when there isn't any friction modifier. Not sure about the "trans X" or those off the shelf gear lubes that tout that they already have friction modifier in them..... I always ran the mopar additive back in my street days with the 8.75. If it was binding up that bad at least you know what it would feel like to drive with a spool.

Posted By: 1_WILD_RT

Re: second time for metal flakes in the gear lube... why? - 08/16/09 05:22 AM

There could also be issues with the parts used to rebuild the unit, there are some out there that are known for problems, I would strongly suggest contacting Dr Diff... He knows the Mopar stuff far better than most...

Posted By: CokeBottleKid

Re: second time for metal flakes in the gear lube... why? - 08/16/09 10:33 AM

Bet your clutches are too thick, get the proper mopar clutches and you'll be fine.

Posted By: Leigh

Re: second time for metal flakes in the gear lube... why? - 08/16/09 02:17 PM

Do you happen to know if the place reversed any of the plates? That was an old trick to really tighten up a Sure-Grip.

Posted By: 67dodge67

Re: second time for metal flakes in the gear lube... why? - 08/16/09 06:24 PM

Got in touch with someone today who is close by and he will be looking at it next weekend. Thanks for all of the input here, I do appreciate it.

Dave