High Mileage Oils--Do they Work?

[burnbomber]

Do the high mileage oils with more seal conditioners work? Anybody got a leaky set of seals on their engine and the higher mileage oils actually stopped the leaks?

I just had the timing belt and front engine seals done on my 3S-FE Camry, and the mechanic said the rear seal leaks too. So, I've still getting oil spots on my driveway. Is there any expectation that an oil change with Maxlife semi-synthetic will affect my leaky 3S-FE?

 

[bobfather99]

Its worth a try to use Maxlife or another hi-mi oil, or you can try A-rx.

I would avoid the "stop leak in a can" stuff at most stores, though...

 

[Audi Junkie]

They work as good oils and help out with seal issues.

 

[kingrob]

If you have a leaking rear main seal, try Castrol High Mileage. I ran two OCI's with Valvoline Max Life and it did little to slow the leak, but one OCI with the Castrol HM actually did the trick. Afterwards it's all I ran in my old Sentra before I sold it, I'd run something else and the leak would come back.

Although I don't advocate stop leak products, I used to use a pint of Marvel Mystery Oil each oil change. That stopped a front seal leak on an old Caddy I had years back. I don't know how, but it did. It was pretty much a last ditch effort before replacing all the seals. I never ended up having to replace them.

 

[crazyoildude]

I have used high mileage 5w30 in two high mileage gm 3.1 and on both of them is really did work i have also used it in many customers cars and i think it helped on most of them but i cant be 100% sure..they are generally blended on the thicker side of the scale and most have seal conditioners and i believe more anti wear agents but have no data to back that up i have used pennzoil hm and my brother uses valvoline hm which he raves about

 

[ThirdeYe]

I've had it stop small leaks on my sister's old 5.7 Firebird Formula and my mom's 3.1 Malibu. It really does work. Now, I'm not sure what would happen if you were to switch back to a conventional, however.

 

[90lsteg]

I had a leak that developed despite replacing the cam seals, rear main seal and oil pan gasket. Decided to try MaxLife syn-blend when my son took the car to college 8 hrs away. Decided to go with !0W-30 and 3 oz maintenance dose of AutoRx given the mileage on the car.

Interestingly the drip went away after 6K plus miles. This was at the beginning of summer. I am on the second run of MaxLife now and no leak so far. Oil consumption has also decreased significantly. Maxlife is what I will be using for this car from now on.

Prior to that I AutoRx'ed using the "old" recommendation of using two clean and rinse cycles. I am not concluding that AutoRX caused the leak!

 

[wileyE]

I wouldn't expect 1 OCI results out of any of them. At 100k I started running HM in my old 5.0l. My only observation is the oil drained a LOT blacker than usual for about 4 OCI's and seems to be getting back to "normal" now. Rear main has always shown a drip, still does.

 

[TallPaul]

Originally Posted By: kingrob
If you have a leaking rear main seal, try Castrol High Mileage. I ran two OCI's with Valvoline Max Life and it did little to slow the leak, but one OCI with the Castrol HM actually did the trick.
It is also possible that it took until the 3rd OCI for the stuff to work and that either Maxlife or Castrol HM would have worked.

 

[kingrob]

Originally Posted By: TallPaul
Originally Posted By: kingrob
If you have a leaking rear main seal, try Castrol High Mileage. I ran two OCI's with Valvoline Max Life and it did little to slow the leak, but one OCI with the Castrol HM actually did the trick.
It is also possible that it took until the 3rd OCI for the stuff to work and that either Maxlife or Castrol HM would have worked.

That's true. But I always suspected it was the Castrol, being that I'd run another oil and the leak would reappear within a couple of days.

 

[mpersell]

I've had at least one vehicle that was a little leaky and Rotella T 15w-40 seemed to help slow down the leaks substantially.

10w-30 was the recommended oem oil.

 

[Camu Mahubah]

Originally Posted By: TallPaul
Originally Posted By: kingrob
If you have a leaking rear main seal, try Castrol High Mileage. I ran two OCI's with Valvoline Max Life and it did little to slow the leak, but one OCI with the Castrol HM actually did the trick.
It is also possible that it took until the 3rd OCI for the stuff to work and that either Maxlife or Castrol HM would have worked.

I second this theory.

 

[TallPaul]

It's very unscientific anyway how most of these events are recorded. I remember in my old motorhome, I had been running Maxlife for several OCIs and then I put in Group III synthetic. It started leaking right after the synthetic was added. Then I put in a pint of some stop leak (nice stuff looked and smelled like M1 ATF) and within 500 miles the leak was gone. I sold it 5000 miles later and the leak had not come back.

So what caused the leak? The Maxlife? Supposedly HM will clean out the gunk and could open up a false seal (an oil clot) causing the leak and maybe that was it. Or maybe it was the Maxlife and the Syn that caused it.

Would be great to get a couple dozen leaky old engines and randomly assign Castrol HM to 12 and Maxlife to 12, run them a few OCIs and see which ones still leak.

But if all HM oils have seal conditioners, then it should not matter if you switch them off. And what Kingrob has shown is that the HM oils as a group seem to be effective, and that is a result I can live with.

 

[ARB1977]

I had two buddys who ran HM oils. One ran Maxlife in a inline 6 ford and the other Castrol in his Nissan V6...both with 300K going strong. Im about to run Maxlife with 3oz of Auto Rx in both Jetta and Tacoma.

 

[Nickdfresh]

All I can say is that I've had a leaky valve cover on a Ponti. 2.2L, and with less than 1000 miles on a current run of MaxLife 10W-30: the leak is all but gone and the car has used absolutely no oil (something I'm not used too coming out of a Saturn

).

After a "short" OCI of 3K, my next change will be 5W-30 Pennzoil Platinum. So we'll see how things go...

 

[TallPaul]

It seems that with HM oils, and with Auto-Rx, results are quite varied. Some are helped, others are not. It may be part that some don't wait long enough for the stuff to work, but there may be other factors that have not been considered that come into play: type of driving, how hot the engine and oil gets, the type of crud buildup, the way the crud has built up, etc. Some of these factors may help explain the success or lack of success for these treatments.

 

[Gary Allan]

Well, I'd imagine that it translates to some "time in country" thing. That is, over the varied usage profiles, you'll eventually see the benefits if you hung in long enough. I may not match the user's perception of "soon enough" and they may figure that it doesn't work.