Clutch chatter

[Arniep]

Had clutch chatter when I bought by Bronco in 92. did two clutch changes, the decided I'd have to live with it. sold it in 01, bought it back in 09 (trashed), clutch was replaced during that time. My plan was to fix the problem. Was talking to a friend, a very good mechanic who checked my driveshaft and showed me the slip joint side play in the driveshaft was excessive. I took it out and sent it to a shop who recommended building a new one. I couldn't get it for a few days so I came home, put it in 4wd and drove it out of the shop. No chatter. My friend and the man building the driveshaft both agree that the driveshaft isn't the problem, but don't have an idea what causes the chatter but it must be something in the rear drive. Anyone have an experience that would explain this?

 

[Skiddy]

at any time did they have the flywheel checked?

 

[Arniep]

I had it turned both times that I did it. Wouldn't consider changing a clutch/pressure plate without checking or turning the plate.

 

[Skiddy]

thought so just checking. how are the mounts t-case, tranny and one that often gets overlooked are the rear springs. curious what tires and gears

 

[Arniep]

springs were reworked (KC Spring) about three years ago, tires are 285-85R/16, 3.50 ratio

 

[Skiddy]

aren't 285's 35" I am not up on metric sizes

 

[Apogee]

aren't 285's 35" I am not up on metric sizes

A 285/86R16 equals 35.07 x 11.22 in inches. That's a lot of tire for 3.50 gears...hard on the clutch. With that said, I'd be going through the rear pinion, driveshaft and rear output on the t-case.

 

[Timmy390]

I dealt with this for 18 years. Thought there was no cure.......Never chattered when locked in 4x4

Lower gears helped. I went from 32's and 3.50 gears to 32's with 4.11's. I changed flywheels and stock clutches but nothing cured it......

TILL

I found my clutch linkage was JUNK. It seemed OK when looking at it but it was JUNK when I removed it and inspected it. The bushings were gone and there was metal on metal. The clutch linkage couldn't hold the pressure plate and clutch solid when releasing the clutch so it would 'chatter".

I replaced the equalizer bar and all bushings and replaced the stock 3 finger clutch with a diaphragm style clutch and pressure plate.

The result was smooth operation for 2 years now.

Tim

 

[langester]

I had a similar experience years ago. I had 3.50 gears and a 3 speed tranny. I got a smoking deal on some 36 inch ground hawg tires. I had a lot of chatter and shortly there after smoked the clutch. My smoking deal was not so smoking anymore. Lower gears are definitely your friend.

 

[Broncobowsher]

Clutch chatter is hard to fix in Broncos. The linkage fights you. As engine torques and body flexes the clutch linkage moves around a bit. That can fight you. The springs in back wrapping up can be a problem. The spring perches on the axle are well known for rounding over as well so even if the springs are fairly rigid the axle can still roll on the perches.

That is not an all inclusive list, but a good starting point with a lot of overlooked wear items.

 

[Skiddy]

yeah when I went to 35's and 3.50's I had bad clutch chatter, changing gears fixed it. a simple test is put it in 4x4 low without the front hubs locked in and see if it helps, not a for sure thing as others have mentioned but maybe a starting point.

 

[Broncobowsher]

2nd gear low range would be a quick test of what 1st gear and a set of low axle gears would feel like.

It isn't exactly a fair comparison. With 3.50 cogs the lack of torque multiplication at the axle means the engine is trying harder to twist in the frame. Even with the same overall gearing.

I have also found that going up a gear would reduce chatter, but that was murder on a clutch. Back to that lack of torque on the driveshaft (from being in an upper gear) helped the chatter.

About the only good thing I can say about 3.50 gears and 35s is it probably flys down a flat highway pretty good.

 

[Arniep]

285s are actually 33 inches. I have NP435 transmission, so my gearing shouldn't be an issue. With my 351W, 2200rpm at 60 mph is ideal. The rear axle issues sound like a real possibility and as soon as I can get it in, I'll check it out. Shop space to work on my own junk is pretty sporatic, as I rebuild wrecks and have to wait for a bay to open up. I'm to old to be rolling around under it outside.

 

[Arniep]

I'm thinking that the clutch arm assembly was a bit loose. Will check that out asap. Thanks for all the replies and suggestions, Arnie

 

[Sporto]

I had clutch chatter for years. Especially in reverse. I swapped clutch, pressure plate (diaphragm style) and turned the flywheel. Installed the traction bars on top of the springs, new driveshafts and a TC rebuild....It just got worse, so I learned to live with it...

A few years ago, I had a synchronizer problem in the three speed, so I swapped it with a rebuilt one and BAM! No more chatter period...Nothing. Smooth as silk...

Dunno if that is an option, but 3spds are cheap and easy to swap.

Rich

 

[Pa PITT]

.. After reading the Guys comments above .. I guess gearing was what fixed mine.. But I got rid of mine when I swapped out my 3 speed for the NP435.
.... I;d always thought that a ne wclutch & turning my flywheel fixed mine.