SURE GRIP 8.75-489/355 .....ISSUE please advise !!!

[CudaK]

Hey
Got 2 separate issues my tech is dealing with on my 73 Cudas rear end....

(keep in mind that the Tech HAS installed the green bearing kit on the axels).

1st off I went on eBay and bought a complete rebuilt 489 carrier with new 355 gears,bearings and rebuilt clutch pack in the sure grip. A week and half ago My Tech at a transmission and rear end shop that I've dealt with for 30 years, installed them into my Cudas rear end.

Result: a loud whine on decel he's pulled and adjusted this unit 3 times .035 shim on the pinion originally on the rebuilt unit. He's gone from .040 "worse" down to .015 and still has the whine....he has assured me that the sure grip,gears,bearings are new and everything as a whole is perfect and he's pulling his hair out on this one.
The guy on eBay says you bought it you own it no returns...anyhow it's got to be fixable RIGHT?

2nd issue I go and order from Quick Preformance a brand new Chrysler 8.75 sure grip carrier, 355 gear and bearing package.. Monday my Tech then installs this in my original 489 case and everything goes in and together perfectly he said.

He goes for a test drive and in a straight line its perfect when he takes a left or right it makes a loud clunk, clunk, clunk sound like damage is being done. Brydon from QUICK PREFORMANCE has talked to my Tech and tells him to start over and use (80-90w-GL5) non synthetic and 2 bottles of (Ford friction modifier). And go do figure 8 in a parking lot.

My Tech claims he did this and it still sounds like its breaking parts around corners loud clunk, clunk,clunk...

Any ideas WTF is going on with both set ups.

Is there something that needs to be removed from the quick preformance carrier there all 30 spline units, the splines go a bit deeper on the QP unit than a regular carrier.

And please explain what the difference is using synthetic or non synthetic gear oil with the Ford friction modifier ?

What should my Tech be looking for doing extra with the QP unit.
And
What do you think is the clunk issue with the install ?
And
What is the whine issue with 1st carrier (gear pattern is perfect) ?

Thanks so much for the info he's going to pull the Cuda back in tomorrow and put a one-legger carrier in for the mean time till the issues can be solved

Thanks for the help

 

[CudaK]

What should tolerances be my techs got it .010-.015

 

[413]

Once a ring and pinion are noisy, they will always be noisy. No fixing it. Your seller knows that.

The clutch plates need to go in a specific order. Look in the service manual, you can see the order they should be in. There are flat and dished plates. If out of order it will be too tight. If it’s too tight it will snap and bang on corners.

I suggest take apart the differential and. Check the stacking of the plates.

I instwlled new clutch plates one time and I didn’t stack them correctly and it broke the spider gears after a while. When it got hotter is was snapping and banging more than when cold.

 

[CudaK]

Once a ring and pinion are noisy, they will always be noisy. No fixing it. Your seller knows that.

The clutch plates need to go in a specific order. Look in the service manual, you can see the order they should be in. There are flat and dished plates. If out of order it will be too tight. If it’s too tight it will snap and bang on corners.

I suggest take apart the differential and. Check the stacking of the plates.

I instwlled new clutch plates one time and I didn’t stack them correctly and it broke the spider gears after a while. When it got hotter is was snapping and banging more than when cold.

Both sets have brand new bearings, ring and pinion and had never been run.

 

[aussiemark]

Green bearings are not good they are ball bearings the original tapered bearings are a lot better they have more surface area and handle side loads if set up with the correct amount of preload they will last a lot longer. I read that there is a spacer in the carrier that must be removed for the axles to be installed properly with the green bearings. If I ever fit new bearings in mine I will go with the Timken tapered OEM ones. Yes a lot of newer cars use green style bearings and do 100k miles with no problems but as a heavy diesel mechanic I have never seen this style bearing used in a haul truck for a very good reason.

 

[Daves69]

A clutch type sure grip has thrust buttons for axles with standard tapered bearings that allow axle end play adjustment.
A clutch sure grip requires removal of the thrust buttons to use axles with "green" bearings. They will not have an adjustment.
It should look similar to this with buttons removed...……..

What has been removed...…….
E-Body 1970-74 - Barracuda - Challenger -- Wheels - Brakes - Rear Axle / Rear Axle - Components / Thrust Spacers /

An article that may shed some light...…….
Why Green Bearings? - Quality Body Shop Drivetrain

 

[CudaK]

A clutch type sure grip has thrust buttons for axles with standard tapered bearings that allow axle end play adjustment.
A clutch sure grip requires removal of the thrust buttons to use axles with "green" bearings. They will not have an adjustment.
It should look similar to this with buttons removed...……..
View attachment 61049

What has been removed...…….
E-Body 1970-74 - Barracuda - Challenger -- Wheels - Brakes - Rear Axle / Rear Axle - Components / Thrust Spacers /

An article that may shed some light...…….
Why Green Bearings? - Quality Body Shop Drivetrain

Ok so you are saying to remove the thrust buttons in the carrier when using the green Berings on the axles... is that what's causing the loud clunking sounds when cornering as it is smooth and no issues when driving in straight line.

I know in the new unit (all new sure grip chuck, gears and bearings) that I got from quick preformance has the trust buttons installed.

The other unit (rebuilt 8.75) does not have them but the gears have the whine on decel, what my Tech said he's tried everything and believes that the ring and pinion gears are the issue

 

[Daves69]

Ok so you are saying to remove the thrust buttons in the carrier when using the green Berings on the axles...

For a clutch LS, yes.

...is that what's causing the loud clunking sounds when cornering as it is smooth and no issues when driving in straight line.

It "MAY" well be if your axles are sporting the green bearings. That's where I'd look first. The tapered bearing set will have an adjustment made from the passenger side axle retainer.

Of course I don't know exact circumstances to positively make that call. Unlikely, but maybe there is an internal assembly issue with the setup. Sorry, no way to know from here!

The other unit (rebuilt 8.75) does not have them but the gears have the whine on decel, what my Tech said he's tried everything and believes that the ring and pinion gears are the issue

Luck of the draw sometimes. If it's too overbearing to run, you might see what the supplier say's about a replacement set.

 

[CudaK]

For a clutch LS, yes.

It "MAY" well be if your axles are sporting the green bearings. That's where I'd look first. The tapered bearing set will have an adjustment made from the passenger side axle retainer.
View attachment 61065
Of course I don't know exact circumstances to positively make that call. Unlikely, but maybe there is an internal assembly issue with the setup. Sorry, no way to know from here!

Luck of the draw sometimes. If it's too overbearing to run, you might see what the supplier say's about a replacement set.

Actually both sets of gears (ring and pinion) set is unmarked except for the ratio 355. Leads me to believe that there on the cheap side. Ordering Yukon gear set on Monday for the OEM SURE GRIP.

And try again.

As for the Quick Preformance carrier I'm hoping they get back to me, and let me know that it's the thrust buttons/green bearing set up that's causing the harsh clunking when turning left and right

Thanks for the info I learn so much on here !!!

 

[CudaK]

Well finally got a appointment with the shop that does my tranny/rear end work and installed the 355 Yukon gear set in my Cuda... what a difference a quality gear set makes, no whines or noise of any kind 6th times a charm

 

[BSG]

i'm dealing with a similar issue with the green bearing failure. I have found the preload spacer that is almost if not exactly like a piece of axel that's about an 1 1/2 wide and looks nothing like the link above, where its a 2 piece button. i'm told i need to remove it so the green bearing don't have a side or preload as all that is built into the bearing. i do have the sure grip. my question is how do you remove it and when removing is there any spacing shimming are diff setup procedures that need to be done or can i simply take some things apart to access the spacer and simply put it all back together. i'm sure someone here has a link to a repair manual that has a rundown of it all? its a rare rainy day here in so cal so its a good day to hunker down in the garage and get something done

 

[Daves69]

I have found the preload spacer that is almost if not exactly like a piece of axel that's about an 1 1/2 wide and looks nothing like the link above,

Is that a "cone" LSD like picture below, typically in the 489 cases?