Regarding the Rotella T6 5W40, I run this oil in my motorcycle, 2003 Suzuki 1500LC with 135,000 kms (I bought it new) and my 2008 Arctic Cat Prowler XTX700EFI with 3500 kms on it (I bought it new) and this oil is fantastic! I wanted to run it in my truck too, 2001 Ram 1500 w/5.2L but it did not spec for use with catalytic converter use, so I didn't use it. Do diesels have cat converters?

 

Grab a bevy of choice and have a read at this site. Going to 0-30 oil today.

http://www.bobistheoilguy.com/cms/

 

i use 5w30 in both of my 318's and they both build oil pressure quick.

 

my oil PSI goes to about 50 on cold start ups......after shes warm, its at 40psi (idle) then when i get on the gas, the needle is just past the 0 in 40

 

If you get bored one day, and have a few bucks to spend..... change your oil pressure sending unit, and see if things change...... Reason I suggest this is..... I had oil pressure problems on my truck, so, screwed in a mechanical gauge. Yep, little to no pressure..... changed to a high volume oil pump, and had over 80PSI at idle on the mech gauge. Put the electric sending unit back in, and the gauge rarely goes much over 40 pounds, no matter engine/ambient temp. I bought a new sender, but, haven't had the chance to install it yet. (don't have the right socket.)

 

I know this thread is old, but I just inherited a '95 Dodge Ram 1500 V8 Magnum 5.9L from my grandpa. I live in central Illinois, and its starting to get into the colder months (its only October and has already been down to 30 degrees F) so I figured now would be a good time to change the oil. I was wondering if I should switch to 5w40 or 5w30 for the winter? The truck has roughly 170k miles, so I wasn't sure if the thicker 5w40 would be better during the winter for high mileage.


One more question, once it gets back into the warmer months should switch back to the recommended 10w30 or switch to 10w40 instead? (since it has high miles)

 

With more miles you want thicker oil not thinner.

Nah, I'd stick with 10w30. I actually started using thicker oil about ten years ago at like 100k. I've used everything from Delo 400 15w40 to Maxlife 10w40. I usually keep 10w40 in it year round but if I know I'll drive to MN in the winter, then I'll switch to 10w30. That's plenty thin. Leave the 5w30 stuff for cars and modern engines. It's practically water anyway.

 

Alright, thanks for the advice. Just to clarify, once it gets to the warmer months, I should use 10w40?

 

Most mechanics would advise thicker oil the older the engine but it's up to you. 10w30 is what came and what Dodge recommended so you can't go wrong. If you have a lot of usage or leaks, thicker is better again. If you have any noises or knocks thicker is better. If you tow a lot, thicker is better. If you live in the south, thicker is better.

 

You are correct, run the 5W30 in winter and 10W30 in summer.