new update, well im somwhat pissed and confused, i went back out and changed my oil and tryed that MMO as soon as i got onto the expressway and went up to high rpm's BAM no oil pressure light on, i very quicky shove it into neutrol and kill the motor, pull off to the side of the road and check my oil, it all looks good right on the full mark, get back in start it up ands its fine, go down the road hit high rpms and again 0 oil presure, i listen, no knocking but a very wierd sound under the truck, shut it off restart and well im good. im starting to see a pattern high rpms 0 oil, but i dont know if it is actually 0, the noise wasnt a knock and losing psi and 75 mph i fig my motor would have blown. my trucks only did this one other time when i first bought it in march and ideas? sender? i really dont want to rev it in park hit 0 psi and listen for a knock what do u think?

 

check your cat. i had the same problem,also the intake gaskets go bad and will make a knock sound that will not send error code to cpu. good luck

 

A couple of thoughts.
Pull the oil sending unit and put a gauge on it to verify what you are getting. The 1/16" hole in the sending unit can get trash and do weird stuff. Would want to verify the reading before continuing to run the motor or digging too far into it. If the oil pressure is correct, plan on new set of bearings, pump, etc. if you keep running it. Pump at least to fix it.
If the timing chain has worn down, the plastic pieces could be starving/plugging the pump.
Wonder if the distributor and drive could be causing both the noise and pump issue.
Couldn't hurt to pull the valve covers to make sure the rear rockers and other parts are not loose and no oil passages pluged.

That would be my first shot at the oil issue. Which is more pressing than the knock now. Or caused it.[:@]

 

from what you describe, your sending unit is going bad. I had this happen on my Jeep with the 318. the sending unit will start seeping oil up thru the connector and contaminate your wiring. yank the sensor off and put a new one on, or do what Chopper1 suggested with the mechanical guage. Also, the MMO will clean the inside of your motor over time... it is possible that something broke loose and is being pushed up against the oil pressure sensor, but I kinda doubt it...

what did the wierd noise sound like?

 

well its all good now it was the sender, also i tried the mmo and wow the noise is 50% better im sure overtime it will be fixed thanks so much for all your help, also customed my exhaust with no muffler and 3' angled out the side right before the passenger wheel so i dont hear anything now

 

was the sensor leaking oil out of the top?

glad to hear it's fixed... the knocking noise is gone now when it's cold?

run mobil 1 15w50 and you should have a happy motor (internally anyway's...)

 

sensor was a little oily couldnt tell ya, and ya when its cold its 50% better i put 4 quarts of moble 1 10-30 and mmo and its sounds a lot better i had 10-40 in there with lucas and it sounded horrible, what should i run with next time 15-50 with mmo?

 

I always run a heavier oil... I'm in Sacramento, CA where we have 100+ deg summer days. I've found that it seems to run better for me when it's really hot out. On your next oil change you could put in 4 qts when the motor's cold, then fire it up and see how it sounds, then go either way (mmo or mobil1) with the last quart. your not going to hurt anything being 1 quart low to see how it sounds. my truck would rattle immediately w/o the mmo on cold starts. it would quiet down once it was warmed up.

 

well i live in toledo ohio where it gets 0 degress in winter and 100 in summer what would you rec in both conditions

 

i'd probably go with 10-40... the coldest it gets here and in the mountains is the low teens and the 15w50 has worked fine for me.