Installation of ring gear to carrier

[Joseph E.]

Is it required to use lock washers on the ten bolts that hold the ring gear to the differential carrier? I'm putting my differential back together on my'65 and the service manual says nothing about lock washers for this application. The instructions in this same manual for a solid rear axle similar to that in a Camaro does specifically state that lock washers should be applied to the ring gear bolts before installation whereas for the Corvette rear lock washers are not mentioned. The bolts are .8125" long and would be have less thread holding the ring gear if a lock washer were to be used. My carrier shows no signs of lock washers being installed on it previously and I don't recall if they came off of the bolts that were taken out of the rear quite some time ago. Thank you in advance for any replies.

Joe

[Wayne M.]

Re: Installation of ring gear to carrier

Joe --- I've got four ring gears (& pinion) sets in my basement, dated from Dec '64, 1966, 1967 & 1973, and they all have the lock washers on the bolts attaching the ring gear to the differential case.

[Joe L.]

Re: Installation of ring gear to carrier

Is it required to use lock washers on the ten bolts that hold the ring gear to the differential carrier? I'm putting my differential back together on my'65 and the service manual says nothing about lock washers for this application. The instructions in this same manual for a solid rear axle similar to that in a Camaro does specifically state that lock washers should be applied to the ring gear bolts before installation whereas for the Corvette rear lock washers are not mentioned. The bolts are .8125" long and would be have less thread holding the ring gear if a lock washer were to be used. My carrier shows no signs of lock washers being installed on it previously and I don't recall if they came off of the bolts that were taken out of the rear quite some time ago. Thank you in advance for any replies.

Joe

Joe-----

Original GM ring gear bolts through at least about 1977 were used with a split lockwasher, No exceptions I know of. These bolts were standard hex head, GM-300M material grade (6 lines), trimmed (non-indented) with a short, unthreaded shank below the head. They were supposed to be 0.78" in length.

Beginning about 1978, these bolts were replaced by a somewhat different bolt for SERVICE if not for PRODUCTION. This bolt was a flanged hex head, also GM 300M material. It was an untrimmed (indented) head. This bolt was not used with a split lockwasher. Instead, it had a serrated surface on the underside of the flange which was, apparently, supposed to provide some locking function.

By the way, if replacing lockwashers on the earlier bolts make sure to use grade 8 lockwashers. Most lockwashers on the market today are not grade 8.

[Gary R.]

Re: Installation of ring gear to carrier

Hi Joe E,
As Joe L mentioned your diff originally had the 6 line bolts and lockwasher. I use ARP ring gear bolts in all my builds and recommend them over the grade 8 bolts and lockwashers that come in the master kits. I find the 77-79 flange head bolts were not set with any thread locker and many of them backed out in use, causing issues in the diff.

If you go with the ARP's clean them with acetone or brake cleaner, same for the holes. I run them in with the RG on the bench to make sure there are no burrs to cause an issue. The case holes are not countersunk so you will have to countersink them a little so the radius under the ARP bolt head clears. I check them for fit before installing the RG. I use Loctite #271 red in the hole and a drop on the bolt. That way the Loctite will wick up the threads when you install them. Torque them to 55-60 FT/LB in a star pattern

[Joseph E.]

Re: Installation of ring gear to carrier

Thank you to those responding to my post about lock washer use on the bolts which secure the ring gear in place on the carrier. I have a supply of grade 8 lock washers and will add these or go the route of using the ARP bolts as suggested by Gary Ramadei.

Joe

[Joe L.]

Re: Installation of ring gear to carrier

Thank you to those responding to my post about lock washer use on the bolts which secure the ring gear in place on the carrier. I have a supply of grade 8 lock washers and will add these or go the route of using the ARP bolts as suggested by Gary Ramadei.

Joe

Joe------


Are you sure that the bolts you have are not the GM replacement bolts with the "serrations" on the underside of the head? If so, those are to be used without lockwashers. In any event, I would use thread locker on the bolts.