Rotella-T 5w-40 in my 3.5L V6 Intrepid?

[cartmanea]

Spec oil for the engine is 5w-30 with 10w-30 listed for warmer climates. The engine has 160k miles and isn't as smooth sounding as it used to be. I've been running Walmart's SuperTech 10w-30 high mileage formula for the past 50k miles and wondering if it would hurt anything to use Rotella-T 5w-40 synthetic so I can use the same as my 6.0L Powerstroke. Please let me know your thoughts!

Also, I plan to drop the pan soon and do rod bearings, would a thinner or thicker oil be best to break in the new bearings?

Thanks!

 

[Gary Allan]

RTS is fine from the standpoint of reducing your inventory. The economics of it depends on how long you're going to keep it in the sump. It's not a bad $4/quart oil ..but if the alternative is $2/quart oil ..

I don't think one oil over another is going to make a difference. You have a crank driven oil pump ..so you're into assembly lube for your first start unless you've got an old oil pump hanging around.

 

[bobfather99]

I say go ahead and use it.

You can use RTS the way its marketed, as a fleet oil for your "fleet". Should work great in both the Intrepid and the Powerstroke.

 

[cartmanea]

Thanks for the input. Anyone else have thoughts?

 

[ewetho]

Probably do just fine.

 

[Ramblin Fever]

I switched my 185k mile 3.2L V6 SOHC Isuzu engine over to RTS 5w-40 2yrs ago without a single blink of an eye, and have never looked back.

Truck runs better then ever, although it never used oil prior to RTS, it did and does prefer heavy 30wts or 40wts, I've never noticed any difference in mpg. Engine is very smooth and seems to have more giddy-up then using straight 10w-30 oils.

 

[Steve S]

It will work but I will ask is there a problem with the bearings? bearings do not break in as if everything is operating as it should the bearing and the journals are sepreated by oil. Kinda like watersking. If the engine is o.k. I would try an A/RX cleaning I have used it and it works .

 

[JTK]

That 3.5L wouldn't skip a beat between a 5w30 or 5w40, but theoretically, the 5w40 will reduce your fuel economy a bit. Do you really want to do that?

Joel

 

[Gary Allan]

It will mainly depend on his miles per warming cycle. If it's a shorter usage car ..then it may add up to something ..but that mainly depends on if it's a "frequent" short usage car.

 

[JohnBrowning]

It will not hurt a thing it sould work very well! Everything I have tried RTS 5W40 in has liked it! If you have not tried Auto-Rx yet now would be a good time to give it a try. I would simply add it when you add the RTS and leave it in their for the entire OCI. When it itime to change the oil do a 1200 mile run with a dino oil just for good measure and then back to RTS!

 

[cartmanea]

Thanks for the input, I'll be going with RTS 5w-40 on the next oil change, however I've never been a fan of engine flush agents so I won't be doing that. The car has mostly highway miles on it, 160k of them, and the oil has been full synthetic for the past 70-80k so I'm not worried about sludge.

 

[Volvohead]

Auto-Rx isn't a flush agent, and that is its beauty. It is a bona fide ester-based crankcase cleanser that improves the lubricity of the host oil as it cleans. Don't confuse it with any other "flush agent".

I would definitely use it here after the bearing service to have a clean start. It also cleans out ring lands, which will keep the engine cleaner going forward.

 

[cartmanea]

I read it works best with Dino oil, should I do a run with regular oil and Auto-Rx then switch to RTS?

 

[Gary Allan]

RTS doesn't have a problem with competing with Auto-Rx for turf. Auto-Rx works with anything really. PAO and ester base oils slow the process and I think it would be way too complicated to tell someone the treat rate/duration/etc.

 

[Volvohead]

Originally Posted By: cartmanea
I read it works best with Dino oil, should I do a run with regular oil and Auto-Rx then switch to RTS?


Unless Shell is putting polar components in the RTS, it is a G-III base and should be fine with ARX. Avoid esters and other more exotic G-IV/V oils with ARX if you want optimum results.

I'll probably use RTS for the next ARX rinse on our 850 (at 200k). But at the short intervals involved, any plain jane conventional will hold up fine.