I am swapping the stock axle bearings to green bearings in a stock 8.75 rear (741 case 3.91 sure grip).

Simple question.

Do I need to remove the stock thrust pin in the center section with the green bearings or just leave it there?

Remove.

Yep.

Yes, just converted the GTS over several months ago.

Thanks for your input guys.....I just got an email from Cass (Dr.Diff) and he said I could leave them in. Now what? I guess it can't be a huge deal either way. I just got done taking them out and have the chunk bolted back in, I think I'll run it as is for now.


*Cass just emailed again, said its definitely ok to leave them out, just that leaving them in was ok too.

I had problems when I left them in the pig on my 64 Dart. I ended taking them out. but, who am I to arugue, Cass is the man when it comes to 8.75 rears.

Going in the yellow car?

you don't HAVE to remove the pin, but i would recommend it.
on occasion the green bearing installation on the axle can locate the axle inwards a small amount, like 1/16". and with the pin still inside it can put constant outwards pressure on the green bearing causing early failure.

this happened to several people i know when green bearings first became available. they had constant bearing failures in a short amount of time until they removed the pin. after pin removal their problems disappeared.

Mr T2U I think Cass does or did have a description of that exact problem on his site The early style (one piece design I think) is still available and moves the axles in too far. The newer style Cass has (two piece with snap ring I think) put the axles at the right depth to allow the thrust block to stay in. Important for Cone Type centers which require dissambly to remove the block.

May have the types mixed up, I just remember two types of green bearings. No doubt Cass already pointed the OP in the right direction there.

Yes, the one I removed was a stock two piece design, nail heads about dime size dia. with a thin connecting pin that slides together. Sure Grip is the clutch style, stock 3.91 741 case. I am leaving them out, will report any issues but I don't expect any.

yes the green bearings my friends had problems with were the early design without snap rings. there are 2 different types. the early ones he used to sell then the good ones he sells now with the snap rings.

Early style Green bearings are just as good as the "newer" style, just that in the past and present most of the installation instructions leave out the detail of removing the thrust button assy, which is there because of the original preload design, leaving it in can/could result in premature Green bearing failure as every axle and install has too many assembly variables to chance leaving them in, I put a set of the original Green Bearings perhaps 30 yrs or more in my Challenger T/A 8.75 rear with ZERO issues to date, every ride I build, customer's or my own toys get Green bearings, I've had ZERO failures with the Green bearings I've installed over the decades, proper installation is key to any components longevity...

Mike

I just had my axles trimmed down at the spline area by 3/32” on each one at the splined end, and that was just the chamfered area, and not the spline. That gave me the clearance that I needed without pulling the centersection out...

The machine shop has grinding lathes, and that is what it took to remove material, and he did not put a chamfer on it, as I did not want to lose spline area. He said it was VERY hard material!

I did my other car like that with the green bearings, and have had no problems.

Mark

I have run 3-4 sets since 1999, followed advice I got from the Doc/Cass and have had no problems running with the thrust block or without the thrust block. I have them both ways.

first set with the thrust block = 9 yrs daily street driving. ran with axle seals.

2nd set without axle seals and no thrust block = 5 yrs and the started seeping thru sealed bearing.

replaced and run axles seals couple yrs now. all good.

installed a set with no seals and a thrust block. failed due to BRAKES over adjusted = heat melted bearing seal/rollers growling. less than 100 miles...I mean super hot!

replaced with axle seals keeping thrust block and CORRECT brake adjustment = 1yr+ so far all good.


IMHO, watch the brake adjustments and DO use axle seals.

I have run fine without seals but in the end it always starts to leak with out them.

LOL! I got one 8 3/4 without seals to service yet. but they have 150,000 miles and no leaks yet at the bearing. I think I leave it alone for now.

BUT. I think I call Cass for a bearing & seal kit now.