Chatter in Rebuilt OPEN Rear Differential

2002 Tundra Access Cab, 4x4, V8, Open rear diff.

As the title states, I've had my rear differential rebuilt recently. This was a pricey repair & my truck started exhibiting chatter when turning at intersections or parallel parking after the repair (did not exhibit these issues before)

The shop who did the repair initially thought that the truck had an LSD so summed it up to a lack of friction modifier. They added the modifier and tried to send me on my way. I insisted that they check through the filler plug to confirm that this was an open diff - and now we both believe that it is an open diff.

The shop is suggesting that I take the truck home and let the friction modifier 'work into the system' to see if it stops the issue.

As I understand it, this is a waste of time as the chatter can be caused either by a lack of lubrication or worn parts or a misalignment maladjustment during the rebuild. AFAIK there is nothing for the friction modifier to 'work into' as this is not an LSD.

I've told the shop to try and get to the bottom of why I'm experiencing chatter in an open diff rather than take the truck back at this time.

Does anyone have experience with chatter in an open differential ? Am I doing the right thing by pressing them to continue to try and resolve this ?

 

I have no experience, but if they can't tell the difference between an open diff and an LSD... you need a different shop.

 

Hey...I was going to say that!

 

Press them.

An open diff won't chatter unless something is not right.

 

This is the answer you seek.

 

When I had chatter due to using synthetic in my factory LSD, adding friction modifier in excess made it go away. But there was still a hint of chatter. That said, I drained the synthetic fluid, put in Lucas 80w90, and the chatter was instantaneously gone. Just one more reason I think that shop is full of shit.

 

Thanks for your replies, unfortunately they are the shop who did the rebuild - and they are the only shop within a reasonable distance (within 1-2 hr drive) who would rebuild a differential. Both Toyota dealers in my area were unwilling to rebuild it.

I agree that an open diff won't chatter unless something isn't right. I've pressed them to figure it out before I pick the truck up again.

What could be causing the chatter in an open diff ? They've had the whole diff apart & rebuilt it completely with new bearings / shims etc (no new hard parts, but apparently those are in great shape).

Thanks

 

If they had the whole diff apart, and it’s an open diff, why would they tell you to add friction modifier???

 

If it's original diff housing and r&p it shouldn't have needed new shims. Just new bearings and crush sleeve.

 

@KNABORES - I didn't give enough context here. The tech who did the rebuild was not in that day. The tech who thought it was an LSD didn't have enough info & made the wrong assumption. I'm not impressed but we all make mistakes.

@assassin10000 I was mistaken, this is what they replaced during the rebuild : Pinion Nut, Pinion Seal, Pinion Bearing ,Crush Sleeve, Washers(?) Side Bearings , Spacer, Inner Axle Seal.

Poking around online - some folks indicate that chatter in an open diff is a sign of damaged spider gears/cross shaft , any thoughts on the validity of that claim ? Just trying to come prepared for when I speak to the shop about next steps .

Thanks folks

 

Spacer and washers worries me.

Could be bad spiders but I'm not there to inspect it. Or drive it, to feel what it's doing.