so i got 94 150 with a 302 i started hearing a tapping but it only does it when im on the at hi revs if i drive normal i dont hear it talk to a guy who works on fords he says its normal and dont worry about it but i dont trust just one person what could it be

 

It could be a hydraulic lifter bleeding down causing a lil slack in between the pushrod and lifter. Maybe a lil thicker oil may help. It will be fine though.

 

what would be a good oil im useing 10w40 high mileage

 

Try 20w 50. Its thicker.

 

Never discount the simple things like an exhaust leak. Are you sure the noise is only at high RPM or is it when the throttle is "matted"?

 

its only does it 3800 or more and its a defined tap tap tap tap tap tap but really fast my oil pressure drops to less then 15 pounds but when i first crank her up its up to 30 then after its warmed up it drops under 15 pounds ive been told by mustang guys that older 5.0s start doing the same thing so its not a rare thing but id like to know what it is i wish not to be crusing threw a river bed and my motor stops

 

How many miles on the engine? At 3800 rpm, your doing some serious work with the motor. More than likely, you have some clearances between the cam bearings and mains. The oil pump may also have some wear. Several thousandths of wear, brings you further down on pressure. The lifter cups where the pushrods seat have also widened up. This all translates into lower oil pressure. If the engine runs fine from startup, idle to cruising speed, you should be ok. I wouldn't go any heavier with oil weight. You may show better pressure, but the time it takes to get to the higher areas of the block will only accelerate future wear. Another idea is to run some MMO in the oil near the end of your oil change. I'd say 1/2 qt at about 500 miles to go.

 

In MHPO I would install a higher volume oil pump.

Small but intresting articale

Ford Small Block Oiling System

 

it was the hydraulic lifter bleeding down and truck has 235002 miles on it

 

Thanks for posting the update and finding/repairing the problem.