Using, not burning oil. (1 Viewer)

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Can some of the 80 series elders share some wisdom as to why it seems a fair number of 80s use a decent amount of oil but do not burn it? My 40 is 30 years old and doesn't use a drop. This is the one thing that concerns me about the 80 I am looking at.
 
Bailey,
There are a lot of things that can cause oil consumption. Leaks where the oil is coming out of a pan seal or otherwise coating the bottom of the truck. I think if it were leaking past the head gasket into the coolant you would be seeing that in the radiator fairly quickly. "Burning" where the oil is being mixed with the fuel and consumed as part of the combustion process. This is the probable cause of the consumption. There are several places where the oil can get into the combustion chamber; head gasket (unlikely,) valve seals, rings, etc. You may or may not be able to see this burning in the exhaust smoke; especially if it is a nominal amount. 1 qt per 100 miles and you can see it. 1 qt per 1,000 miles and you probably won't see it in the exhaust.

Toyota, and most manufacturers, have a very liberal view of excessive oil consumption. IIRC, Toyota considers 1 qt per 2,000 miles as "normal."

As a point of reference, my normally aspirated '97 has 122k miles and consumes less than a quart per 5,000 miles. I drive like an old grandma according to my wife. :D

-B-
 
B-

MR T says one quart or less per 1,000 miles is normal.


Cruisin, Often vehicles APPEAR not to be using oil. Un-burned gasoline "finds" it's way into the crankcase and "replaces" the oil that has burned. As a result, it looks like it hasn't used any. Then if you hop in it and take off on a long hiway trip it gets hot enough for long enough to evaporate all of the gas that's in the crankcase. It gives the appearance that "all of the sudden" it's using a bunch of oil.
 
[quote author=Beowulf link=board=2;threadid=3657;start=0#msg26716 date=1058221127]
I drive like an old grandma according to my wife. :D
[/quote]

Of course, with a 3FE I have no choice but to drive like an old grandma...

-H-
 
-H-,

Think of it as a governor, then it's not so bad on the old noggin. :D
 
I used to drive from Northern NM to Flagstaff and back in a 1976 FJ40 about 6 times per year. If I could get to 55 mph I'd feel like I was making good time. If I didn't have to crank both heaters crossing the Painted Desert to keep from overheating I was stoked! So now that while still driving a Land Cruiser, I can cruise at 75 with the CD cranked and the A/C on I really can't complain!

-H-
 
I lose about a quart per every 3500 miles. Whoop-di-doo!

I just add a quart of M1 and change the filter and let her eat another quart before the next full oil change. :D
 
Somethin was up with your 40 then, I can drive mine in 85 deg weather for 3 hours on the highway while pulling a trailer with one atv through the mountains and the needle won't even see the "normal" range. Theres no telling the last time the coolant was changed or even what mixture of antifreeze/water is in there. Other than the fluctuating oil pressure my F runs like top. :D Thats why I'm suspicious of the 80 burning oil, but it seems common so I'll deal with it until I rebuild the engine so I can put a blower and water injection on it :eek: :D
 
Bailey-you may be maligning 80's unfairly! I don't know of any that use much if any between changes. I use about 1/2 quart in 5k miles which I hope is perfectly normal. If you found one that does use oil, it was probably neglected for part of its life, find another. In my own case, I changed oil and filter before Cruise Moab, drove there (900 miles) and back and couldn't even see a change on the dipstick.

My 60 on the other hand leaks a bit, probably burns a bit and I add a quart every 1500 miles or so. It still seems OK.

Keep looking for that perfect 80-they're out there.
 
I guess I was being a little hard on it, it must be difficult to be compared to the best truck ever built ;) :))
Seriously, I do feel that the truck was very well taken care of, the owner who is the original owner knew about cruisers and what needed to be done (birf repack etc). He sites a Jiffy Lube overfilling the oil as the reason for the oil consumption. If I can get the cruiser for up to 9k I will be very happy, after my mechanic checks it out and I check out the difflocks.
 
>> He sites a Jiffy Lube overfilling the oil as the reason for the oil consumption. <<

Bailey,
Did the owner elaborate or give his theory on what is going on?
-B-
 
[quote author=Beowulf link=board=2;threadid=3657;start=0#msg26786 date=1058248960]

Bailey,
Did the owner elaborate or give his theory on what is going on?
-B-
[/quote]
He said that he took it to a Jiffy Lube type place to have the oil changed, he then drove it for about a thousand miles, checked the oil and realized that they had overfilled the engine. He then drained and refilled it to the proper level himself. He said that ever since then it has used a quart between oil changes. Depending what he considers the proper interval between oil changes, I may just adjust my oil changing schedule so that the loss of oil is not significant enough between changes to have to add some in between.
Is his theory viable? He didn't go into anymore detail than that.
 
If you're using the thin-as-water 5w30 dino, I think it tends to vaporize easily. Think of it...the base is really a 5 wt oil!
 
[quote author=Beowulf link=board=2;threadid=3657;start=0#msg26786 date=1058248960]

Bailey,
Did the owner elaborate or give his theory on what is going on?
-B-
[/quote]
He said that he took it to a Jiffy Lube type place to have the oil changed, he then drove it for about a thousand miles, checked the oil and realized that they had overfilled the engine. He then drained and refilled it to the proper level himself. He said that ever since then it has used a quart between oil changes. Depending what he considers the proper interval between oil changes, I may just adjust my oil changing schedule so that the loss of oil is not significant enough between changes to have to add some in between.
Is his theory viable? He didn't go into anymore detail than that.
 
[quote author=Jim_Chow link=board=2;threadid=3657;start=0#msg26861 date=1058283826]
If you're using the thin-as-water 5w30 dino, I think it tends to vaporize easily. Think of it...the base is really a 5 wt oil!
[/quote]
I'll have to check on that, I bet hes using whatever the owners manual recommends though. ???
 
I just went to 15w40 to see if the motor uses less oil than 10w30. I see that the motor uses more oil at red line ( when the tranny is on power).
kurt
 
Bailey,
Overfilling the crankcase is not good but linking that to the "new" increased consumption is a little harder to understand. I suppose the overfill could have resulted in aerated oil (crank spinning in the oil) and consequently the aerated oil would cause increased wear.

I dunno.... it's possible. Any lubrication engineers want to give their thoughts?
-B-
 
Bailey have you tried crawling under the 80 to see what the seals look like. From what I heard when I was searching the main seal is likely to be weeping at that mileage although that's not a major concern.
 
Not all rear mains leak. :D

During my front axle overhaul the truck had to sit for over a week and there was not a drop to be found (okay, but only a couple :D) afterwards.
 
The guy assured me that it had no leaks whatsoever, and he did tell me about 2 problems it had/has (starter/oil consumtion), so I am assuming him to be somewhat trustworthy. Tomorrow I am offerring 8 and if he takes me up I will then extensively check it over before I hand him the check.
 

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