How much oil use is too much?

[Goose]

Just made an 11 hr trip in my '85 6.5 na truck with 4.11 gears. I think I ran close to 2800-3100 rpm all the way. I used about 3/4 qt of oil and 2 qt of coolant. (all the coolant is gone from the overflow jug, radiator still full)
The oil I kinda expected with the higher rpm, not so much the coolant. It was 80-90 degrees they whole way and I ran about 195-205 on the thermometer.

I've heard of head gasket going and pulling coolant into the oil. With both the oil and coolant being lower what should I look for?? Or should I even worry?

[john8662]

You probably have an external coolant leak. Old radiators leak coolant and because it's so hot the coolant usually evaporates before touching the ground, showing you the leak. Of course, it could be other areas that are leaking, look at all possible coolant junctions for chalky appearance when dry, that could show you where the leak is.

J

[Goose]

I'll check externally then, thanks.

[trbankii]

To check for coolant leaks, Autozone has pressure testers in their rental/borrow "fleet" of tools. If not familiar with the program, you basically "buy" they tool, but they fully refund your money when you return it. Just did that a couple months ago with my own truck to chase down some radiator leaks. Replaced the radiator, but due to time constraints I patched up the leaks with some JBWeld so that I could get it through the state inspection without it "peeing" all over their shop floor... :)

[Goose]

I'll have to look into that. About 10 yrs ago I redid my rear bearings in a 12bolt using the "buy it-return it" program at Auto Zone for a slide hammer gear puller.

I think I'll start with the expansion tank 'cause it seems like it would be the weak link.