When driving my oil pressure gauge drops .if I'm at. Light and rev up to get the rpms higher,it goes back up but not long. It's been heti worse.

The low reading may be due to low oil level or a faulty oil pressure sending unit. A shop can test/replace the sending unit if that's the cause. But also be aware if you have the 4.7 V-8 engine, it had a tendency for the small oil return passages to clog up and the engine would starve and fail from lack of oil circulation. You may be hearing ticking and knocking sounds at that point. An "engine flush" may make it even worse by releasing too much sludge all at one time, clogging the oil pump screen too. It might be worth a few dollars to have it evaluated by a good mechanic and prevent an engine failure. I hope it is nothing serious.

I had this problem with my 2001 Grand Cherokee, with the 4.0 six cylinder engine. After about a year with this dropping oil pressure problem, the engine finally blew out (sounded like a very large hammer pounding on the inside!). The car had 135,000 miles when it happened. Beginning maybe a year earlier, the pressure gauge began showing normal pressure after starting, and then drop after the engine ran for awhile, and then the gauge would almost bottom out at lower RPMs, with the warning bell going off. After getting incomplete answers, and spending a lot of money trying things like replacing the oil pump, I drove the car about another 10 months, but not that many miles, before the engine went out. After that, I talked to an older, very experienced mechanic, who knew exactly what the problem was when I explained what happened. He told me the bearings were starting to go out when I first started experiencing the dropping oil pressure. He said it is not uncommon for these Jeep engines to get failed bearings. He is not a fan of them! Very upsetting, expecially given that the car had regular oil changes with top-grade synthetic oil (maybe that's the reason it ran as long as it did), but the mechanic said Chrysler used low quality bearings, and there wasn't anything that could have been done to correct that. I found the following information after talking to the mechanic, which explains more: "Loss of oil pressure is also one of engine bearing failure symptoms you need to know. Normally, the oil pump flows a fixed amount of fluid (which is 20 gallons per minute). If there are some little leaks in your engine such as leaks in the gap between your engine bearings, the rocker or the hydraulic lifter, your engine will lose oil pressure due to oil coming out of the oil channels. Hence, excess clearances between the bearings as a consequence of excess bearing wear will lead to loss of oil pressure, especially at low RPM when the pump is spinning at slowest speed."