xterra oil change surprise

[2005tundra2002yz250f]

Changed the oil in the xterra today. a 2001 with the 6 cyl, has used amsoil 10w30 and mobil 1 10w30 since 7000 miles. It has been given 4000 oci's with the mobil1 since it only has a 3.5 quart capacity. The oil has always been to the top level on the dipstick(terrible dipstick, thanks nissan), and not very dirty at all, brownish, but not bad at all when changed. So today, I checked the oil level as I always do, and its barely registering on the dipstick, and is black. Not the darkest black you can get, but close. Plenty of oil came out, Id estimate 3 quarts, so it wasnt very low. I did see some "sludge" on the drain plug, something else I have never seen previously.
So now I think I may have missed a change somehow, but even if I did, at wrost case Im at 8000 miles. My question is, to those that go 7500 miles on mobil 1, does your oil get black? I know color does not indicate if the oil is good or bad, and my engine differs from everyone elses, but I want to know if in a good running engine, does your oil go black at these intervals?
Seeing the condition of the oil at that interval, if it indeed was 8000 miles, would make me never go for that long again in this engine. If it wasnt 8000 miles, then I have problems I guess! Truck now had 64,500 miles.
Time for a UOA on this truck after 5000 miles I guess. Also time to start writing down the miles on the trucks when I do oil changes/maintence. I was always ok going by memory, but I guess Im losing it at 30. **** .
Thanks

 

[Gene K]

Nissan V-6 is a great engine but is known to be kind of dirty. ie it tends to make oil look pretty bad.

Gene

 

[Brett Miller]

Mobil 1 was jet black after 5,000 in my S-10.

 

[Bror Jace]

Bogatyr use Schaeffer 5W-30 in his '01 Xterra.

He posted a couple of UOAs for the beastie on this forum.

--- Bror Jace

 

[stang5]

on my pathfinder V6 with 3 1/4 QT capacity is the same thing with either amsoil or M1, The oil gets dirty real fast. one time I ran it on amsoil for about a year with about 9K miles, with no UOA, that was before I found this site. Gives me the chills just thinking about it, now I'm doing a ARX treatment after that I'm going to use Amsoil and then M1 and compare the UOA.

 

[Palut]

Just last week I checked my '85 Accord, and its oil (Pennzoil LL 15W-40) was black after 4800 miles. Not so black that I panicked, but black enough to say that, this needs to be changed! Of course, I believe this engine has lots of blowby, as it was abused before I knew anything about oil. (starting the engine at -25 F with 15W-40, and driving less than one mile, repeated dozens of times!)

 

[sdude2k2000]

I've got a 2000 Nissan Frontier (same motor) as you, and i only let my oil go about 5,000mi... because it does tend to get a bit dark.

But in all fairness to that, the motor is great and has obviously proven itself over YEARS of service

 

[ekpolk]

Which of their V-6s goes into the PF? If you haven't, run a search over in the UOA section to see if anyone else has had problems with the small capacity. If you're one of the anti-UOA crowd, you might reconsider. The value in UOA is not in deciding whether to run your oil longer (although that can be a reason). It's more like the lab work your doc might run on you at a physical. In the present case, a UOA will either set your mind at ease, or perhaps alert you to a problem that has arisen but that you might not discover otherwise until more serious symptoms have emerged.

By way of comparison, my VQ35DE, which has a 5 quart capacity (in a G35, don't know about other applications), is approaching 4k miles on its first fill of syn (GC) and 10k overall miles. This oil is barely past the blonde stage; looks very nice. And yes, Nissan dipsticks are awful!!!

 

[lobo11]

Does anyone out there offer an aftermarket oil pan with more capacity? 3.25 qts. wouldn't make me feel very good, I think I would definitely run synthetic in that baby!!

 

[Geoff]

I would check/replace pcv valve. It can affect crankcase pressure, sludge, etc.

 

[berge]

quote:

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Originally posted by 2005tundra2002yz250f:
[QB] The oil has always been to the top level on the dipstick(terrible dipstick, thanks nissan), ]

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I have the same idiotic dipstick in a 99 Quest.
How are you checking the oil level, because, the only consistent reading I get on this engine is FIRST PULL after an overnight drain. If you pull the dipstick, wipe clean and reinsert, the reading is always different. Usually almost 1L higher.

 

[Cary]

I have a 1991 Pathfinder which uses the same basic motor as the Xterra and holds about 3.5 quarts per change. I have been using M1 at 5000 mile intervals since I bought it as 127k miles and it now has 190k miles. Runs great, no problems. I regularly run into guys with over 250k on these motors and they just run whatever oil and change it whenever. I wouldn't be to worried. If you are do a UOA as someone suggested.