Have a 94 GMC Suburban that just dies while you are driving. What could be wrong?

SOURCE: sudden change in oil pressure gauge

It is normal on a Chevy for the oil pressure guage to fluctuate based on the rpm's of the engine. The faster the engine is turning, the higher the pressure. If it is fluctuating without a change of engine speed, then you may have a REAL Big problem such as low or no oil in engine or the oil pump itself is going bad. Could also be a blocked oil filter. You surely change your oil regularly....right?

SOURCE: 1993 GMC Sierra C1500 5.7 just recently started

Most likely the Gage is not the problem these rarely go out. If the pressure is only dropping then the oil pump is getting weaker or is filling with sludge. Try running the engine with an oil additive such as marvel mystery oil or sea-foam. Then after the additive has circulated through the engine for a few heat ups and cool downs you can change your oil. the pressure should change almost immediately. If it doesn't then check the oil pressure switch. You can look on the side of the block and there will be a small piece shaped like a pencil with a wire coming from it. This piece is the oil pressure switch. Hope this helps. Please rate me if you think this helped. Good luck.

SOURCE: Gas gauge inoperative

The sending unit in your tank is bad replace it.

SOURCE: low oil pressure 93 GMC P/U w/350 motor w/205,000 miles gauge

While engine is running, open the cover where you add oil to engine and see if you see a good flow of oil, if good flow, could be as easy as replacing oil sending sensor. got to realize that if poor maintenance history your engine may not be building enough pressure at iddle to move your hydraulic operated valves, only when you rev it up it will pump enough to run smooth. if running engine too long, you may cause more damage to other engine components such as crankshaft and cam shaft bearings. if you can spare a few bucks, have a good mechanic check your oil pressure with a mechanical gauge. another cheap option is to replace oil pump. last resort if you love your truck as much as we do,replace engine or rebuild it. At 205,000 this is a normal symptom, other than timing chain problems, most engines don't make it that far. hope this helps!

SOURCE: oilpressure gauge indicates low to almost no oil pressure

You may want to hook up an external oil pressure gauge
to the engine to ease your mind. This would give you a regular number of the pressure. Compare it to the factory gauge in the dash. Those in dash gauges were not all that precise. If the engine is not having bearing noise I can see nothing to worry about.

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