Synthetic in the rear diff.

[jasonvibe]

I am about to change my rear diff. oil. I use synthetic gear oil in the rear of my shaft drive motorcycles. The difference of deposits on the magnet drain plug is obvious when using a good synthetic. I was wondering how many use synthetic oil in the rear? Some people warn when using sythetics in trucks with limited slip rears. "You may experience chatter". Can anyone tell me if I should be worried about using a synthetic..aka chatter ? Thanks in advance...J.

[keithvibe]

I just changed the rear diff fluid out and put in synthetic oil. I have not had one issue with chatter yet. I used amsoilhttp://www.amsoil.com/storefront/fgr.aspxIf you do experience chatter you can add:http://www.amsoil.com/StoreFront/ada.aspxALSO I did a quick right uphttp://forums.genvibe.com/zerothread?id=30721

[jasonvibe]

chatter is most noticed on wet. Not really noticed on snow covered roads. When just wet and you "gas it" Say to get into traffic...you would feel a "grab, no grab ". It's similar to driving on wet leaves, slip, no slip then slip again. But all in the space of less than 2 seconds. I have felt this on trucks with limited slip. But in the snow...it's hard too detect in the snow. I was thinking of using 75w90 syn. or 75w140 syn. There are many around. Everyone knows the second # is the hot or extreme condition rating. Just have not made up my mind yet on wich to use. Oh the other reason for me using synthetics. I just don't put than many miles on. The cars is driven mostly short distances. So the warm/cool down cycles are many. I saw your "how to on the rear diff". When did you do it? and have done the "gas it in the wet" yet?...Oh you may want to add...the torque spec. is 29 ft/lbs for the plugs. I see yours were marked.

[keithvibe]

as a matter of fact Jason I have checked it on wet. I haven't experienced any chatter. Today, it's snowing and raining and I punched it a few times and haven't had one issue with chatter. Just hooked up and went.I did the change on the date stamp..10/28.I do have to disagree on the torque settingshttp://www.amsoil.com/scripts/...indexUse the link above and put in your cars info and it will tell you what you need to knowIt states Transfer case Fill Plug.....36 ft-lbs Drain Plug.....36 ft-lbsYou may be confusing it with the Manual transmission which is 29ft-lbs

[jasonvibe]

I just read what was on my Matrix manual. The front transfer case is 36 for its' plugs...the rear diff.says 29 for it's plugs.The rear diff is not the same as the transfer case. Theese are 2 different size plugs. I triple checked.

[keithvibe]

that could be the difference... for some reason toyota states different statssuch as wheel torque. vibe manual 76ft matrix 78ft lbs Don't think the few lbs difference will matter much though

[jasonvibe]

be careful with any alumium...there is a big difference from 29 and 36. I will mark mine before I do it. I did do the front a while back. I marked it and 36 ft/lb lined up with the mark.The front really handles the load 99% of the time. So I put the best gear oil I could find in there....oh, thanks for the info.