How much oil is too much?!

[Mike Tonon]

I had my oil changed and after it was about a quarter inch above the top hole in the dipstick. Is that going to blow gaskets? What does the top hole, mean? Is that the absolute top of the safe range and the top of the hashes/X’s is where it ideally should be? Thanks

 

[Mike Tonon]

Thanks for all the help, guys!

 

[Dirtman]

You are most welcome.

 

[ericbphoto]

I’m sure there is some room for error. How much? I don’t know. 1/4” is probably ok. The level on the stick changes when the vehicle is not level and that rarely causes trouble. Of course, it’s not hard to drain some out.

 

[alwaysFlOoReD]

I have overfilled regularly on an oil leaker I had. I cannot say it did any harm, but who really knows?

 

[Dirtman]

You spent like 3 months discussing the proper mix of differential and transmission fluids yet took your truck to a jiffy lube for an oil change...

 

[Mike Tonon]

No, dirtbag, I had free oil changes from the dealer, from when I bought the truck there 12 years ago. They use synthetic blend and usually do a good job.

 

[rusty ol ranger]

Youre better off being a qt low then a qt over.

That being said the 1/2qt or whatever yours was over shouldnt of hurt nothing.

 

[racsan]

I never worry about being “a bit” over. Think of it this way, you check the oil with engine not running. When it is running it’s in circulation and there’s possibly 1/2 qt of oil NOT in the pan because it’s on it’s way to the rocker arms or other places, so it’s doubtful that even at 1/2 a qt over you’d be churning the oil up with the crankshaft counterweights and rod ends. If I have a capacity of 4-1/2 qts, I’m still putting 5 in (like 4.3’s in S-10 blazers) I’ve never had a issue doing that.

 

[ericbphoto]

I never worry about being “a bit” over. Think of it this way, you check the oil with engine not running. When it is running it’s in circulation and there’s possibly 1/2 qt of oil NOT in the pan because it’s on it’s way to the rocker arms or other places, so it’s doubtful that even at 1/2 a qt over you’d be churning the oil up with the crankshaft counterweights and rod ends. If I have a capacity of 4-1/2 qts, I’m still putting 5 in (like 4.3’s in S-10 blazers) I’ve never had a issue doing that.

Seems to me that the guy designing the marks on the dipstick would/should have thought of that.

 

[adsm08]

Being over won't blow gaskets. It can slow the crank, but on a big engine like that you won't really notice it.

The bigger issue, and this is more of a problem on an automatic trans than an engine, is it can allow fluid cavitation that can effect the pressure in the system.