Running heavier oil's in high mileage cars

[CBR.worm]

What if you have a tap that becomes light knock after some long WOT runs and then goes back to a tap as the oil cools a bit.

This is with M1 0-40, with M1 EP 15-50 the tap is only present after spending lots of time at redline. OE recommends 5-30

The tap became audible at about 90K and is slowly getting louder, but not yet to worry level, but the tap seems to come from the bottom of the motor - not valvetrain noise.

Car has almost 130K on it, most of it's miles are either easy long highway miles (22mpg)or hard highway miles towing a 1,500 pound trailer (17mpg). lots of time in deal's gap (10mpg). Occasionally a track day is thrown in for good measure (12-14mpg).

 

[hattaresguy]

Nope never saw a need to. When the mains are really worn and its about rebuild time a heavy oil sometimes helps get a few more miles out of a tired motor.

 

[bradepb]

I am currently trying a run of durablend 5w-30 in the escape,. I bought it used with 35,000 on it, it now has 85,000 on Motorcraft 5w-20

Since it is a relatively light 30 weight I want to try it because for all I know it may have been abused- not changed etc. If I bought the vehicle new I would run the 20 forever unless problems arose.
I am sure it would live a long life with either but not knowing the history I feel better with a slightly heavier oil that is approved for use in the engine outside the US anyway. Valvoline Europe recomends durablend 5-30 for this vehicle.
For our cold winter I will do one run of 5w-20 Dec-March

 

[SteveSRT8]

we switch oil weights based on consumption between changes.

That's it. No magic mileage or anything, just if the level drops faster than a quart per interval. All our changes are by olm, and probably hover around 4500 miles or so.

 

[mechtech2]

Not just bearing wear, but pistons, bores, rings, valves, and valve guides can wear. Also leaks .
All of these can be helped by a thicker oil.

 

[Merkava_4]

Originally Posted By: mechtech2
Not just bearing wear, but pistons, bores, rings, valves, and valve guides can wear. Also leaks .
All of these can be helped by a thicker oil.


I've been reading the UOA archives and I see some engines that are
in desperate need of thicker oil. Especially those 5.3L Chevy V8's.

 

[Cyclops]

My thought as well. It seems logical that as parts loosen from wear that using a thicker oil film would help prevent acceleration wear.

Doug