I need a new summer oil. I'm running Rotella T 15W40 in my IROC and I freaking love it!

I was wondering if the 10W40 version of it would be suitable for the ole ticking 4.6...


thank you

 

10w40 should be fine. My neighbor has an expedition or excursion, can't remember which, but he's running 10w40 in it.

 

Do you hear that???

It's the sound of a can of worms being opened!

My opinion: Wrong Weight & Wrong oil composition. I'm not sure if the rotella T has the proper gas engine certification for ford. If I am wrong someone will let me know. (Labnerd)

Rotella T is a great diesel oil. And it is only called Rotella in the US.

 

Have you ever really checked on what the reccomended oil is?
5w20 from Ford.
The timing chains are hydraulic tensioner adjusted.
To much tension for to long from the heavey oil wears things.
It's not just heavier is better with theses engines. Other things come into play with this different engine design..
Noise means there is something wrong--like wear!
Trying to cover wear with heavey oils dosn't cut it.
If you live in a winter climate, good luck starting with the heavey oils.
I'm not trying to be smart but only to get you to look at it the modern way and not the way of the old days.

 

Ford recommends 5W20 for efficency purposes. Its assanine to put that light of an oil in. When I worked at Ford, every tech said it was bull**** and they were running 10W30 and 10W40's in the summer, in their motors.

 

....

 

No offense, but Its probably better to run 5w-20 then 15w-40.



If your really worried about it, I would go 5w-30.


Rotella can be used in a truck/pick-up, but why would you run a heavy duty oil with advanced soot control in your Sports car?

 

I am running 5W30 in the truck, but its summer, and it needs to be changed soon, and I want to go thicker for the summer.

The IROC gets 15W40 cause I am still in the break-in progress on the flat tappet camshaft. Its got a built 350 and with this sort of cam, calls for the thick, high in Zinc Rotella.

 

5W30 is the correct weight for your engine, 10W30 is acceptable in warm weather. What's the difference between winter and summer? With a 180 or 192 degree thermostat, your engine is running at the same temperature once warmed up regardless of the ambient air temperature.

 

Start up is the difference and it is a big one depending on where you live.

 

Right - and I was asking why the OP wanted to use heavier oil in the summer. The "W" weight really doesn't make a difference in the summer - it will start fine on 0W, 5W, 10W, or 15W.

 

Guess I'll move up to 10/30

 

In the summer, there is essentially no viscosity difference between 5W30 and 10W30 - the W rating is at 0F and the 30 rating is at 210F.

 

Camarothatcould, I assume that you are talking about your 98 Ford. It is speced for 5w-30 oil meeting the now current 929 spec. I would not suggest putting the Rotella in it. I think you have the wrong info anyway, Rotella that you are talking about is a 5w-40 or a 15w-40. Either will be thicker at temp than the design perameters for your engine. The oil and internals will run hotter, not cooler as a thicker fluid does not absorb and release heat as quickly as a thinner fluid. The 5w-20 oils will run far cooler when things get hot under the hood. You also have more fluid being pumped as thinner fluids move faster to the job than a thicker fluid so there is more lubrication using the thinner oils. Many years ago we recommended the heavier oils because the oil film strength would break down under load and heat. The heavier oils had better film strength. No so with todays oils and the 5w-20 oils will have greater film strength than the 15w-40 Rotella due to the basestock used. Either stay with the 5w-30 or use the backward compatible 5w-20. I'll bet the noise goes away with a run of the 5w-20.
On your GM engine. I hope you have a LARGE supply of the Rotella in CH or CI API rated oil. The new CJ oils (for low sulphur engines)will be missing the additive package that your modded engine needs. Have you looked into CD2 Street Legal Oil Boost? It can be had a some of the Dollar stores and is full of the add pack you will be needing. Also, GM Oil Booster, while not cheap, is another alternative for you. Or, for now anyway, using an oil high in ZDDP like Amsoil could be an alternative.

 

It's amazing why these people cannot upgrade there thinking from from the 'old world' of oil thoughts.
The 10 weight is higher viscosity upon starting and until the oil gets fully heated.
Guess that dosn't count for inital lubing when it actually accounts for a lot of the engine wear over time, at each cold start.
85,000 on 5w20 with a lot of towing in the heat of summer at gross weights over 11,000 lbs. and the motor has no ticks, knocks, or other noises.
Tell me I need heavy oils!