Slipping clutch...due to high rearend gear?

[AKcharger]

Last weekend I zipped down and got to work on my car for a weekend but on way back to storage I notice that if I floored it at 70 MPH in 4th I could get the cluch to slip when the 4 bbl kicked in.  I did the whole 4 speed swap in Oct and put about 300 easy miles on it to break the clutch in, this visit I was a bit more agressive. It grabs great in all other conditions. All brand new clutch parts including fly wheel behind a mildly built 383.

So is this likely a clutch  problem or could the 2.76 gears I'm running be the cause? I know the highest gears Chrysler would use with a 4 speed was a 3.23

Oh, it does get 19 MPG 

[John_Kunkel]

How much pedal free play?

[AKcharger]

maybe 1 inch at the pedal..all seems good

[XH29N0G]

I doubt the gears would be the cause of the slipping.  I would wait to see what the others say. 

I had a similar thing happen with a new clutch and it was a faulty clutch.  If I remember correctly, one of the pads wore off and the rivets that held it on contacted the flywheel (metal on metal would not grab).  It dug grooves into the flywheel which was bad. 

I hope this is not the case for you.

[Charger-Bodie]

Had that happen a few years back when I bought a cheap hays clutch  . Had it behind a 383. Ended up buying a better clutch set up and that cured it.

[kab69440]

Did you have the flywheel cut? A new clutch disc likes a fresh face to wear in with.

[AKcharger]

McLeod clutch, should be of good quality? didn't face the fly wheel since it was new...didn't think I'd have to?

[kab69440]

I suppose the possibility exists that the new face could have been too smooth. Admittedly, I wouldn't think to cut a new one either. Other than that, the pressure plate may not be sprung heavily enough. Is the over-center spring installed under the dash?

[Paul G]

A silly question but, did you use brake clean on the faces of the pressure plate and fly wheel to get the oily protective film off before install?

[AKcharger]

- Kab Over center spring is NOT installed
- Not silly Paul, anything can be overlooked...but yes it was degreased

[A383Wing]

hope you didn't burn off the disc because you had to slip the clutch so much with those high gears.

Bryan

[AKcharger]

hope you didn't burn off the disc because you had to slip the clutch so much with those high gears.

Bryan

they're not THAT bad

[Cooter]

Sounds like Weak Pressure Plate. Maybe good enough for "Light driving", but "Spirited" driving blows 'em out even with my T-5 and 440.

[elacruze]

Has your transmission input shaft seal leaked into the clutch?

Mine has, previously.

[AKcharger]

Has your transmission input shaft seal leaked into the clutch?

Mine has, previously.

Hmmm Not sure. The real bummer about the car is I din't notice it till I was driving it back to storage and Im not going to see it again till Carlise in July. Will be nice to finally have it home!

[c00nhunterjoe]

2.76 @70 mph is no where near peak power. You shouldn't be able to slip the clutch there. Odd that it doesn't slip at any other times. It is definatly flairing? I'd check for a rear main or trans seal leaking oil. Mcleod is good stuff! I'm running a centerforce dual friction behind mine and it held good on et streets with no slips. Good enough to bust my windshield and rip the driver door striker out of the jamb....lol which model mcleod did you buy?

[AKcharger]

I'm thinking the leaking front seal is the most likely culprit, i know the rear main is/ was tight and dry. The trans came out of a '66 charger and it is super tight so I'd bet the car it came out of was wrecked in the early 70's and sat ever since so dry rot of the seal is a real possibility.  So with that in mind:
- Is changing that seal as simple as pulling that "snout cover" to swap out the seal our is it a more involved process? ( well have to pull trans of course )
- if it is oil contamination, is the disk ruined or can I clean it up with solvent?
- pressure plate should be  ok right?

Thx

Sorry joe can't recall exact model, standard 10.5 inch I believe

[Chryco Psycho]

the front seal is in the front brg retainer & is easy to change out if that is the problem .
if there is oil on the disc depending on the material it may be ruined although they will usually grab if there is oil on them like brakes do pressure plate should be fine unless there is a problem mechanically causing it not to apply full pressure .
If you have the 130 tooth flywheel I would have ordered the 10.95" system , the 10.5 is too small for the 440 .

[elacruze]

If your clutch disc is oil-soaked, you can cheap out and give it a good soak in acetone. If it looks good afterwards, it probably is-it's an old trick we used for forklift brake shoes, which seem to have a systemic problem with axle seals regardless of brand.

[AKcharger]

Good tips. Thanks guys!