[KLG]

Originally Posted by OzzieSS

Yes and yes to those two questions. My garage floor is perfectly level. I let the car sit for 30 minutes which ten qts showed low, barely on the dip stick. I then let the car sit overnight and still got the same reading as before. This means either GM's golden rule of 10qts is complete foul or they need to get tighter specs in terms of their dip sticks in regards to where the proper oil level readings are gathered.

No other ifs, ands or buts about it. Going by the dip stick tells me my LT1 isn't properly filled with just 10qts.

For sure your garage floor is close to level side to side. However, if your garage floor is like mine, your garage floor is sloped slightly towards the garage doors to allow water to run out. But, that ever so slight slope should not make much difference in the oil level reading on the dip-stick. You could test by checking the oil level with the car pulled in and again with the car backed in.

Regardless, if 10 quarts just barely touches the dipstick and does not make it into the cross-hatched area, I understand your concern. However, you can be sure that your oil pan/crankcase is essentially identical to mine. There is not enough difference in manufacturing tolerances to give your oil pan a significantly greater capacity than other LT1 engines.

Now, if you only need to add a few ounces of oil to get the level into the cross-hatch area, that is probably not a big deal. If you’re adding a quart or so, that would be concerning to me.

Here is the level on my dipstick with 10 quarts of oil and the car backed into the garage. Tough to see since the oil was just changed, but it is just below center of the cross-hatched area.