I was driving back from the desert at about 70mph in triple digit temperatures when the top end started sounding like a sewing machine and the oil light came on. I stopped and did a check on the oil level etc. and restarted with no problems. The water temp guage was normal. Drove again for about 20 miles and it happened again. Since I got back to LA (below triple digit temps) I have been driving for about a week with no issues at all. Any suggestions from the experts? I was thinking some kind of sensor is breaking down in the extreme heat possibly...

The vehicle never uses any oil between changes and always has a clean smog.

1998 with 193,000 miles

Thanks
Alan

 

Stop driving it before you gernade the engine.
How mechanical are you?

 

fairly mechanical but no place to work on it. What did you have in mind?

 

This is SOOOOOO common on these engines everyone should know of it by now.
You have excessive engine sludge, when driving for long periods with sustained higher engine RPM the oil cannot drain back to the oil sump fast enough to supply the engine with oil, so the oil light comes on.
Shut the engine off, oil returns to sump, you check the level and it is fine.
Drive around town, rpm's are low, oil drains back to sump fast enough to keep engine sump full.

Since you have no place to work on your truck, at least for serious work, take it to a shop to have it de-sludged.
Whatever they want, pay it.
BUT make sure they also remove the oil pan and clean the oil pick up screen.

Again, this is common on these engines, usually from using the wrong motor oil over a long period of time.
Even with proper oil change intervals using the wrong oil will cause excessive engine sludge.

Outside temp had nothing to do with it.

 

This is not a oil pump issue, this is not a clogged oil pick up screen issue, this is not a motor oil issue.
This is a excessive engine sludge issue.
Using the wrong motor oil will cause this issue over time, but it has nothing to do with his issue right now.
Breaking loose a ton of sludge all at once can clog the oil pick up screen.

If the correct solvent is used it will re-liquefy the sludge so it can be removed from the engine.
Find a shop that has the machine that hooks upto the engine and removes the sludge.

The other option is adding a can of Gunk engine flush 2 blocks from the oil change place.
Have then change the oil and use diesel engine oil, then do several 500 mile oil changes.
After that stick with the diesel oil and have it changed every 5,000 miles and no more.

 

OK, Spike is the optimist and I am the pessimist, it is a thankless job, but...

We know the oil light came on at higher RPM over an extended period. Could be sludge, could be other evil things (cracked oil pump), clogged pickup, air slurping pickup, etc.

The oil fills part of the valve covers and drains down through "galleys". If sludged, it does not drain as fast. I had a Chevy that was so sludged I had to dig it out with a spoon and use a rod to push down thru to open up the passages.

If solvent engine cleaning works, great. But the possibility of the oil screen covered in gunk is there, and all might not come off with solvent. If you are paying someone to look at it, spring for the oil PSI test, replace the oil pickup O-ring, clean the pickup, lock tite bolts for same. A pair of gaskets for valve covers and you can see what is going on from the top down.

 

If it was a cracked oil pump or clogged pick up screen the problem would be there all the time, even in town and not on a long trip.

 

[quote
The other option is adding a can of Gunk engine flush 2 blocks from the oil change place.
Have then change the oil and use diesel engine oil, then do several 500 mile oil changes.
After that stick with the diesel oil and have it changed every 5,000 miles and no more.[/QUOTE]

Thanks Spike, are you suggesting adding the solvent then only driving it for 2 blocks with the solvent in it and then immediately having an oil change? I have noticed that the oil never goes black between oil changes [at every 3000 miles] it stays quite clear which I believe indicates that it's not doing its job of engine cleaning.

 

I have used GUNK engine flush before on a Mazda MPV that I had, you are supposed to put it in and idle the engine for 20 mins and then do a oil change.
You are not supposed to drive it, but you can in the city at low engine speeds and low engine load you will be fine.
The oil change place will also have a engine flush but they will charge you $20 for a $5 bottle.
After you have the oil changed have it changed again a week later and make sure you use ONLY diesel engine oil in a 15w-40.
It is highly detergent and will slowly clean your engine as you drive.

 

Thanks Spike, Use diesel engine oil in a non-diesel vehicle?
Alan