4.0 Engine Oil Capacity ?

[thumpin455]

I just changed the oil for the first time last night on the 95 Aurora I bought last week. The owner's manual lists crankcase capacity as being 7.0 quarts but mentions that up to .5 additional may be needed considering the filter change. I have a hopped up olds 455 in my other car with a 7qt moroso pan so I have a good idea what 7 quarts of oil should look like in the big drain pan I have been using. The drain pan looked really full so I poured the old oil into plastic milk jugs for a measure and just as I expected, 9 quarts including the oil from the filter. My dipstick reading before the oil change was not over the full mark. As a matter of fact it was registering within the normal operating range one notch below full on the dipstick. With 8 quarts of new oil and a filter my dipstick reads dead on the add line. Adding one pint would put it half way between add & full which would equal 8.5 quarts. To get it to the full line it would take at least 8.75 quarts. I noticed that there is an oil cooler in the radiator in addition to the tranny cooler. Could it be that this oil cooler really holds around 1 and 1/2 qts or is the manual just wrong about the crankcase capacity. Just curious if by chance the dipsticks were too short in 95?? Anybody notice that latter year 4.0's also hold 8.5 to 9.0 quarts total with a filter change??

Thanks, Paul

[Indy8]

This was a factory blunder. Yes, the early sticks were too short. The true recomended capacity w/ a fresh filter is 7.5 quarts. 8 will not hurt it. The oil cooler is factored in. It's hard to ignore the stick, but if it will make you feel better, completely drain,add new filter,add 7.5 qts. start it and let run a couple minutes, shut it down, let it settle, and remark the stick as full. All years have the same capacity. Looks like someone didn't know this and went by the stick before you bought it. Cams are up top, so you don't have to worry about the lifters going hydraulic, and I think I've read in a Northstar article that a windage tray was designed in due to the high RPM capability of the engine. So hopefully no damage was done.

[thumpin455]

Thanks Indy8, I am glad you are on top of things here. This is the type of important issue I would have expected to find discussed in a previous post. I read pretty much all the Aurora threads on this site prior to buying my 95 and didn't come across anyone ever mentioning that the early dipsticks were too short. All is OK here seeing as I stopped at 8 qts then posted this thread.

Thanks again,
Paul

[Indy8]

You're right, the last time this was covered was at the old GM Forums site. Unfortunately, two or three senior members did not make it over here when they shut it down and we all lost out on the posted info as well as the extra input. So far, this site just has not been the same. No offense to anyone here, it's just like breaking up a championship team. Maybe over time, all of us here will gel like that.

[magyar]

I hear ya Indy8...we lost a lot of good info when the old site shutdown. I wish I had saved it all. Damn.

M

[dsatt12]

Huh, here I thought my '95 just used oil all this time. I'd wait at least a few weeks after an oil change before checking it, thinking I KNOW it's full, then always seemed to be adding a quart. Live and learn...