Rear Differential fix.......maybe

CoachBoone · 07-30-2004, 02:46 PM

An amazing turn of events regarding my rear differential that I was told had metal pieces inside. I was told originally that they found metal chunks in my diff and they were going to replace it. Then yesterday they tell me that no, it was ANOTHER Titan that was in at the same time that had pieces everywhere. Turns out my RD just keeps cooking the oil and even bubbled the paint off the cover. They let me drive it home while they conferred urther with Nissan. Today the local tech-head calls me and tells me that Nissan is now recommending going to a synthetic gear oil to alleviate the heat problem. Has anyone else heard of this? He couldn't give me the new oil specs, but we're crossing our fingers. I looked in the RD yesterday and it looked immaculate, not a shred of wear, it's just a thermal problem. I must say that I was surprised at how small it looked, I thought there'd be more meat back there. And the rear window regulator should be in next week, so it won't sound like crunching nails every time I roll the back window down.
One last thing.....I have heard a nasty whine that sounds like the power steering pump ever since we got back from our big tow. Has anyone had steering pump problems here?

GETSOMZ28 · 07-30-2004, 02:59 PM

Most of us have already put in Mobil 1 75w90 (filled to the correct level). I would recommend that or Redline 75w90 if you can find it.

CoachBoone · 07-30-2004, 03:30 PM

what caused you to switch? I'm not very well versed in lubrication, did you have RD problems? Heat? Does synthetic oil disipate heat better?

GETSOMZ28 · 07-30-2004, 03:33 PM

No, I didnt have any problems. The stock fluid was a little low (checked at 500 miles) and sludgy, and since I had some extra bottles laying around I just decided to swap fluids out (I prefer to use Redline, just didnt have any on hand). I am sure the Mobil 1 (or any synthetic fliud) has a higher flash point than the stock fluid.

There is a post showing the Mobil 1 does reduce the temperature of the rear end.

CoachBoone · 07-30-2004, 03:58 PM

I'll give it a try.

bestatchess · 07-30-2004, 04:03 PM

juma advises in another thread that there is (hopefully) an extra capacity finned aluminum rear diff cover in the works. Also, temps of 240 F on the rear diff have been reported after heavy towing in hot weather.