Is anyone using 10W-40 Full Syn. motor oil in their Car and what brand?

 

10W-40 is usually not the corrrect grade for a 4th gen unless it is high mileage. However, since yours is boosted it's something to consider, especially if your engine has some mileage on it. Do you have any temp. or pressure gauges on the car? If so, are you seeing any indications that a xW-30 isn't holding up to 12 lbs. of boost? Others will probably disagree with me, but a high quality 5W-30 or 10W-30 should hold up fine, and I wouldn't go to a thicker oil unless you were seeing indications of a problem. Thicker is not always better.

The only full syns I know of in a 10W-40 are Amsoil and Redline. Redline also has a 5W-40 available, but it's harder to find. Another consideration might be Mobil's Delvac 1, which is a 5W-40 as well.

 

Hmmm. I got 130k miles and I got NOS. Engine doesnt burn any oil yet.. I should be fine with Mobil 1 5w30 right?

 

Right now I'm using royal purple racing 21 which is the equivalent of a 5W-30 wt. I've had it in for 300 miles and now I hear the chain guides slapping around and I think a heavier oil will stay up better.
Don't forget I have a built engine with 9-1 compression, heavier valve springs and a JWT cam and the rev limiter set a 7200 rpm and I occasionnally use a 65 shot of N20. I have an egt sensor placed at the Y pipe junction and I routinely register 1200-1450 degrees that far from the exhaust manifolds. Also I live in vegas so the bottom line is my car can run very hot when I rod it and an oil like a 10W-40 redline syn. should be beneficial. Am I missing something??

 

I did take into account that your car wasn't stock, but I didn't know it was that modified. It sounds like you're having issues with a 30 wt. By using a 10W-40, oil pressure will be raised slightly and might help eliminate any chain noise. 10W-40's also tend to have much better HT/HS numbers, which sounds like it would be extremely beneficial in your motor. On a side note, by using a 40 wt. oil in this engine, your pumping losses will be increased slightly and your oil temp. will run slightly higher. That's the tradeoff for better protection.

I'm not a big fan of Royal Purple. Most of the feedback on their products comes from people making claims without any data to help back them up. It might be great oil, but I see much more information on Amsoil and Redline than I do on RP. Not knowing much about RP, I would say that the safer bet is staying with either Amsoil or Redline in this case. Those oils should be more cost effective also.

 

If you're not having any issue with it, there's no reason to switch. The only thing you might consider is using the 10W-30 instead. With M1, the 10W-30 seems slightly more stable than the 5W-30.

 

I'm agreeing with Mark here, I have yet to see an impressive Royal Purple oil analysis, especially in its racing form.


My recommendation:

Use a 10W/30, either Amsoil or Redline. Both will serve you well. Both retain their viscosity range, won't shear down significantly, and a 10W/30 will tend to stay higher in a 30 weight viscosity range than a 5W/30 would.

Even given your conditions, I'm not convinced a 40 weight oil is necessary. For a xW/40, I would go with Mobil 1's 5W/40 "European" formulation due to its availability (any AutoZone will have it) and its more rigorous testing standards compared to Mobil's SuperSyn formulation.


More importantly, you should consider at least periodically taking an oil sample and having it analyzed. That will let you know better how your oil changing has affected your engine than anything anyone here could speculate.

 

Car: 97 Maxima 5 Speed Manual
Mileage: 120,000
Oil Used: Castrol GTX 10W-40
Location: Southern Mississippi
Driving Habits: Fast Acceleration
Mods this month: Warpspeed Performance ypipe,bpipe,

Question: What are my oil recommendations? I plan on changing to Redline Syn 10W-40 is this a correct decesion? At this point what should I select? After reading the post I wanted to make and educated deceision considering my driving habits, location, engine mileage and the exhaust mods I will be getting in a week or so.

 

Ron, using a racing oil, from what I know, is not a good idea in a stret car because the detergent package is minimal, street applications need detergents. I use RL 10w30, it seems to be doing just fine, I have done some oil tests and its doing good, better than Mobile 1. I am considering switching to RL5w40 in a few oil change intervals to see if it helps or not. I'd say give RL10w30 a shot for a few oil changes, I go 6k with good results with RL. If that dosent help try the RL5w40 or RL10w40.

 

A full syn 10W-30 would be better. It's closer to the correct grade and won't thin as much as a dino 10W-40 would. 120k isn't really high mileage for a good VQ, so unless you're experiencng significant oil consumption, a 10W-40 isn't really necessary.

 

Valvoline makes a 5w40 - they say it's full synthetic....

 

Recommedation for my car?

Car:'95 Maxima GXE 5spd.
Mods: none

What oil do you guys recommend for my application?

 

5W-30

 

Valvoline's synthetics are just like Castrol's "synthetics". They are a Group III base, which is not really a full synthetic, but highly refined petroleum stock.

 

I have just over 100Kmi on this car and it seems that by 2k mi after an oil change, my oil gets very dark. I don't use a particular brand. I know the mechanic puts in the right amount and it's 10w30 non synthetic.

Any suggestions to prolong my oil changes?