Rear Differential fill capacity?

f00dstamps · 12-23-2005, 04:29 PM

i just changed my rear diff and i filled it with a little less than 2 quarts of Amsoil 75w140 synthetic severe gear oil in my 2005 Titan 4x4 with the OEM finned cover.

the manual says it's 2.125 quarts.

do you guys think i'll be alright? i plan on checking it in several days to check the fill level. how much oil did your guys' diffs take? my driveway isn't perfectly straight but it is pretty darn close.

Herbpov · 12-23-2005, 06:11 PM

First time I changes mine with the old black cover it took 2 1/4 quarts. With the new PML cover it took 3 1/8 quarts. Not sure about Nissan's finned cover. I would think it should be over 2 quarts though.

f00dstamps · 12-23-2005, 08:20 PM

man, that has me worried. i hope someone else chimes in.

i also noticed that my transmission temperature gauge reads a lot lower. before it used to sit at about 45% of full hot... but now it's about 30-33% of full hot. i think that's a good sign.

Herbpov · 12-23-2005, 08:32 PM

Quote:

Originally Posted by f00dstamps

man, that has me worried. i hope someone else chimes in.

i also noticed that my transmission temperature gauge reads a lot lower. before it used to sit at about 45% of full hot... but now it's about 30-33% of full hot. i think that's a good sign.

They say you're suppose to fill it and then go to a parking lot and drive in a figure 8 a few times and then let it set and recheck the level. You only do this if you have drained the rear end. Otherwise just top it off.

f00dstamps · 12-23-2005, 08:34 PM

thanks herb. i'll try that tomorrow.

Mustard · 12-23-2005, 10:38 PM

Not sure how the new diff cover is designed. I just fill it until the fluid runs out the fill hole, do the figure 8 crap top it off again and forget about it.

FlimFlamMan · 12-24-2005, 09:56 PM

Basically the same result for me when I did mine a couple weeks ago. Have the '05 finned cover. Used exact same oil. It took only 3 ounces out of the 3rd quart before it started to overflow (on level ground).

I did not do the figure 8 thing. I'll top it off soon. Cant imagine getting much more in there.

How did your factory oil look, f00dstamps? Mine looked pretty sick after only 5k miles.

f00dstamps · 12-24-2005, 10:00 PM

Quote:

Originally Posted by FlimFlamMan

How did your factory oil look, f00dstamps? Mine looked pretty sick after only 5k miles.

i changed mine at 5600 miles and it looked very different from the amsoil that i added. the factory fill had a dirty gray color. i didn't have a reference to compare it to. the amsoil i added was a honey brown color. hopefully it isn't raining tomorrow, i'll do the figure 8's and refill it.

does the figure 8's go for filling the front diff too? the manual says 1.7 quarts and i put about that much before it was overflowing. i'm not sure if i have enough in the bottles to do a refill for the front.

Herbpov · 12-24-2005, 10:15 PM

I'm just going by the instructions I got with my new PML cover. They said to fill it up until the oil seep out of the fill hole and them go drive in a figure 8 to distribute the oil in the rear end and then top it off. Take it for what's it worth.

f00dstamps · 12-25-2005, 12:12 PM

alright, well i went to run some errands, did some figure 8's and then parked my truck on a small incline so i could fit additional fluid inside. i ended up putting almost another quart in. all in all, i probably put around 2.5-2.75 quarts. is there such a thing as overfilling the rear differential?

TitanTech659 · 12-25-2005, 06:00 PM

There might be a pressure issue if you overfill it. May cause axle seals to leak. When the rear end warms up, pressure goes up. I've replaced axle seals in 2 Titans in the past 7 months and that is the only explination that we could come up with due to the low mileage of the truck.

f00dstamps · 12-25-2005, 06:02 PM

yea, i was afraid of that. i guess i'll go do some figure 8's and then open up the fill hole and let some gear oil ooze out.

JDMTITAN · 12-26-2005, 12:19 AM

Quote:

Originally Posted by f00dstamps

yea, i was afraid of that. i guess i'll go do some figure 8's and then open up the fill hole and let some gear oil ooze out.

actually i don't think u'll have a pressure issue, as long as fill the from the fill hole util it start to seep out slowly, then you know that it's basically full, or you can just squeeze in what you have and let it seep out until it doesnt seep anymore then put the drain plug on. hope that helps

FlimFlamMan · 12-26-2005, 09:20 PM

Well I just went and checked the rear diff level (because I never did the figure 8 thing after changing it) and to my surprise it is still right at the top of the fill hole. I thought for sure I'd have to put a little more in there. All in all I got a grand total of 68 oz in there... and I have the 05 finned cover. Doesnt seem right but everything looks fine.

Bluto · 12-27-2005, 08:59 AM

Just did my parent's 05 with 12,800 miles. I opened the fill hole first (good rule of thumb). Diff had some pressure (or vacuum), hissed a bit. The original fluid level was not up to the drain hole. But I could touch it with my pinky. The used oil was like dirty honey. Not burnt, usual crud on drain magnet. Replaced with M1 75W-140. I used about 2.25 qts. But I spilled some out fill hole twice to make sure it was full.

What is the purpose of figure 8s with an open diff? The oil is not very thick and should fill the diff evenly. Figure 8s make sense to work the clutches in a LSD.