Mix Synthetic Differential Lube brands?????

luvrbus · October 05, 2011, 07:31:09 AM

Brian,aviation Permatex (no 3- 5) is all I ever use DD made a huge mistake back in the 80's when they said use RTV on the back plate people still use it as they don't have the service bulletin to upgrade their service manuals DD stopped using the the RTV and went back to gaskets and aviation Permatex never saw a DD put together with silicone that didn't have leaks

Boomer · October 05, 2011, 01:16:50 PM

Common differential leak is the studs being loose, should always tighten them before mating the drop in to the housing. I always use the red Permatex aneraobic gasket maker on the threads, DDC also has a good product. Torque the studs and nuts to GFT (good and f....g tight), lol. Another thing I recommend to bus nuts since we don't put many miles on a unit is to seal each side of a componant that is coming off for rebuild or repair. Common maintenance practice in commercial service is just put sealant on the componant side to reduce clean up but we usually only have to do these jobs once, better to eliminate all chances of a leak. JMHO

luvrbus · October 05, 2011, 01:48:59 PM

That is strange Boomer in the Rockwell school they told us never use any type RTV except the 3-Bond TB 1216 or Loctite 5699 Gray,they prefer a gasket but if you use RTV use those were the only RTV Rockwell approved but the red must have worked for you.

Most leaks I find are caused by people using a .20 cent Ace Hardware washer I had a terrible time with Smith trying to use the cheap washers on the differential case on his bus lol

good luck

Boomer · October 05, 2011, 01:54:26 PM

You must have misunderstood Clifford, I always use a gasket and never silicone.

luvrbus · October 05, 2011, 01:57:37 PM

I guess I did Boomer didn't sound right to me you using silicone lol

good luck

bevans6 · October 05, 2011, 02:06:48 PM

I think Boomer was saying to install the studs with red Loctite stud sealer, which is what I do too. I use aviation AN washers, they have a couple of different grades and hardened ones if you are putting enough torque on to crush a plain flat washer. I also use split lock washers made for socket head cap screws if I need a lock washer, they are very tough little guys. Glad to hear you like the Permatex Aviation gasket sealer!

Brian

rv_safetyman · October 05, 2011, 03:41:09 PM

Wow, lots of good discussion. I decided to wait to reply until I had done more investigation.

First of all, the silicone issue is interesting. I lost a rear end just before I went on the road in 2006 and installed it myself {fun

}. I have tried to remember what I used for sealing. I am pretty sure I did not use a gasket. My best guess is that I used "Right Stuff" gasket maker.

Before I left Evergreen I replaced the bottom plug as the original one was damaged and it looked like it was leaking. I also tightened the pumpkin bolts (very little to no rotation). When we got to IA and I got the Shell Spirax, I put about 3/4 of a quart bottle in. I am pretty sure that it was a bit low before I left.

During our journey over here (Greenfield, OH) we stopped at a couple of Wal Marts and I did not see any puddle. I just crawled under and checked the level and it is full. That is after about a week and 600 miles. Looks like I don't have all that much of an issue. I will check it a few more times as we travel to Chattanooga and home.

Thanks for all the input.

Jim