About to do a change up and want some advicerinos. I noticed after 3-4 runs my oil pressure dropped 4-5psi as it got hotter, and Im currently using 10w-30 in the SR. Im thinking about switching to 15w-30 or 10w-40, obviously there are tons of opinions on the interwebs about this, but I thought Id ask some locals to see what works well for you guys. TIA

i use rotella in all the sr's i work on. but 6 psi at idle is not bad.

6psi sounds kinda low? I know the FSM says 11 minimum but Im sure there are other factors that come into play. Isnt Rotella diesel oil? What weight do you use?

I really can't say what Im at psi-wise since Im using the stock FC sending unit and cluster gauge, and who knows how accurate that is. When it says 30psi I could be at 15 or who knows what else. The drop at high temps is kind of concerning me though, and Im thinking some thicker stuff might help.

the drop is normal. only comes in 2 wiegths think and thinker. use the 15w40 but it comes in straight 30 too. if you don't want to use deisel oil then don't use it.

is there a benefit to using diesel oil?

Rotella is good for diesel and gasoline engines, it's very stable, resists temp breakdown, extra detergents keep the engine clean.

this has been a topic that's been bugging the V8 guys for awhile now.

Oil used to have zinc in it, but they changed it about about 3-4 years ago and took the zinc out.

Somehow without the zinc in it, when the v8 guys who had flat tappet-style cams would break in a motor, they kept wiping out cams and lifters.


Diesel oil still has the zinc in it, so they started running it during the break-in period, and so...the cams were saved.


I think it might help out the import motors too, but I'm not sure. That's all I know on that subject.

this would be why. also it is cheap.

I am currently running 15w40 in my Rb25det per Matts recommendation. And no ill effects thus far, third event down. I do however need to change my oil though, it is starting to get dark.




p.s. Matt can do NO wrong in my eyes, helps everyone out when they need it. Whether he likes you or not.

I assume this is something that would have to be ordered from a special vender and not your everyday auto store, right?

Chris, I've seen Rotella at Walmart, Pepboys, Vatozone...

Good! I'll pick some up and give it a try. Thanks

Weight-wise, do you think switching to something thicker would help with the pressure drop? Sure the drop is normal but if I could minimize it while still being OK with cold starts and normal driving id like to.

running a thicker oil especially in the summer is always a good idea, mainly due to the hot summer ambient temps thinning out the oil. So a thicker oil would be more prone to keep your moving parts happy. Yeah, Chris you can get it pretty much anywhere. I always get it from Advanced when I go get all my stuff.

I really appreciate the advice from everyone, ended up going for Rotella 15w-40 and a huge ass PureOne filter. Fat mamma jamma brought me to just over 5 qts.