Advice for using Rotella T6 5w-40 in '05 Buick LeSabre

[NauticalMiles]

Wondering if the higher zinc content in Shell Rotella T6 5w-40 heavy duty diesel engine oil would work okay or better in an '05 Buick LeSabre? When I purchased the oil, the reviews read that it works well in gasoline engines, but I didn't consider the stronger detergents and how they might affect my engine. Can I mix the 5w-40 and 5w-30 to dilute the Rotella oil? Thank you for your expertise and information.

 

[Brian123]

Wondering if the higher zinc content in Shell Rotella T6 5w-40 heavy duty diesel engine oil would work okay or better in an '05 Buick LeSabre? When I purchased the oil, the reviews read that it works well in gasoline engines, but I didn't consider the stronger detergents and how they might affect my engine. Can I mix the 5w-40 and 5w-30 to dilute the Rotella oil? Thank you for your expertise and information.

If your car is not an Oil Burner, go ahead and use the Shell Rotella T6 5W-40!

How many miles are on this 05 Buick?
Are you the Original Owner?
What motor oil's have you used?
What are your OCI's like?
If you are not the Original Owner, how many miles were on the car when you bought it?

 

[NauticalMiles]

If your car is not an Oil Burner, go ahead and use the Shell Rotella T6 5W-40!

How many miles are on this 05 Buick?
Are you the Original Owner?
What motor oil's have you used?
What are your OCI's like?
If you are not the Original Owner, how many miles were on the car when you bought it?

Not the original owner. It has a Jasper engine, 241,000 Miles ...I think it already had 200,000 miles when I acquired it.
It does use some oil, but perhaps normal. I've used 5w-30 in the past. That's is in the manual.
Been noticing some warmer engine temperatures last summer, but nothing that gave the computer a warning. Only have owned and operated about 2 years so still getting to know this lovely, old gal. Friend helping me to put in a new water pump, thermostat and rear brakes next week. Other than that this car has been good to me. Well, besides the new battery, alternator and starter last summer but I think I was probably taken for a loop by the GM dealership mechanic...

Thank you for responding!

 

[Rogueman2016s]

Can’t high zinc content harm catalytic converters? I’d personally stick with any off the shelf 5w30