98 Trans AM Oil Problem

You need an engine rebuild. Bearings are shot.

Based on the limited amount of information that you provided, I offer the following:

If your engine has not been damaged due to this condition you can rule out smoked mains as posted.

Depending on engine type, you should be able to drop the oil pan to get at the oil pump. You may have to disconnect a motor mount (drivers side if my memory serves me) and slightly jack-up the engine for the pan to clear the frame cross member.

Rather than just replacing the oil pump, you should do some research. Check with your local dealer, chat rooms, bulletin boards ect.

This is somewhat of a common problem with aggressively modified engines on this model (multiple year series) when run at high R's. There are anti-cavitation plates available as well as other devices for the lower end of your engine to prevent this from occurring.

DISCLAIMER - If you elect to R&R the oil pump this way, MAKE SURE the vehicle is properly supported to prevent the vehicle from falling on you while you are under it causing serious injury or death.

I am going on many assumptions here - Good Luck!

Not knowing which engine you have in the vehicle, some have the oil pump driven behind the crankshaft pulley. If that is the case , not too bad a job.

Lets have some more information.

What has changed since the engine was working correctly?

What oil are you using?

How much mileage is on the TA? How hard is that mileage?

If the oil pressure only goes away at high rpm, you may not have sufficient drainage back to the oil pan. Pull the valve covers, and check for the drainage holes in the head castings. If needed, use shop air pressure to clear a good passage for return. If there is any accumulation there, you may need to inspect the area under the intake manifold for drain restrictions also. THINK about this. If you have oil sludge built up on the interior surfaces of the heads, and valley area, you also have that same sludge built up in the oil pan. That will lower the volume of oil in the pan. Less oil in the pan will allow the oil pump to suck air before the oil drains back to the pan. The best way to determine weather or not the pan is loaded with sludge is to bring the oil level exactly to the full mark, and measure the amount that you drain. Double check by measuring the amount of oil it takes to fill it up again. Exclude the volume of the oil filter for this measuring. Good luck.

the engine is a LS1,has over 100,000 on it,I can run it normally on highway and it seems fine,when running at high rpm such as dragstrip the oil pressure drops ,guage goes to almost nothing,lifters sound ,can stop,check oil and pan is full,run synthetic 20w50 oil,was told by chevy mechanic that early LS1 engines had oil pump problems with a seal ,oil pump is on the front of engine,was told to put oil pump in with new seal,was told could be done without dropping subframe,thought someone might have had this problem before,runs to good to replace or rebuild ,dont use oil.at least not over a quart in 3 to 4 thousand miles and no smoke,thanks for info

What options do you have? If you drag the car hard enough to collapse the lifters, you have starved the mains, and rods as well. How many times do you think you will get away with that? Asa crutch, you can add another 1/2-1 quart of oil, and see if that helps. Another better crutch is an Accusump. It will store a quart of oil when ever the engine is running, and oil pressure is up. As soon as the pressure starts to drop, the pressurized stored oil will flow to the oil galleries to maintain oil pressure until the pressure builds again,or till the stored oil is gone.

There are companies that have sprung up around the LS series engines, that know all of the idiosyncrasies of the engine. One of the companies that I am aware of is Mast Motor sports. You can reach them at 1888-446-4134, or www.MastHotRod.com.