2004 yukon awd- 5.3 i have no oil pressure- new comer to this! need help!

[johngypsy]

first off, i just would like to say, i so wish i would of seen this site a few moths ago, its an amazing place to me as i a am a gm lover, always been-

i will be giveing you a full description about the whole thing, almost the same as other threads, but a little different:

i have bought a 2004 yukon in sc last year with 199k in mint, state condition throughout,for 3100 cash, the reason was the guy had no oil pressure, it would start to tap at start up, and then fade away in less then 10 seconds, or after driving it, well, since 1 and 1/2 years, drove like a dream, if im at a stop, it would go down to zero, and at full throttle go up to 43 percent, and a charm bell that got me so mad, never got used to it yet!

last month, i drove to fill it up, left the station, and as i was driving, the suv started to tap, and tap, at full throttle, and the noise never went away! added oil, still the same, the oil pressure also remained the same, as day 1 i bought it? at this point im at 221k miles, drove it home at 5 miles an hour, parked it, and got a new oil pump installed, after the install, started the truck up, and same issue! tap, and tap, oil presure remains the same, slight smoke from tail pipe, paid 475 dollars for all installed with labor, new oil, and all gaskets, had it professionally installed.

now! im kicking myself, should of bought a used motor for 400 more installed! what am i doing wrong? sending unit? oil lines?

the mechanic gave gas, let it warm up, and slowly reved up the motor to 3,4,5k RPMS, and the oil pressure guage still reads low to 7 percent, and revs up to 45 percent at the most, and still tapping like heck! WHATS HAPPENING?

ANY HELP WOULD BE GREAT! AS WE DO LOVE OUR YUKON, AND DONT WANT TO SPEND MORE NOW,
THANK YOU GUYS SO MUCH,
JOHN G,

[Blackpearl]

What type of oil are you using? Might be able to get something thicker might help. Personally, I'd start saving for a 6.0L

[blacstar]

at 199k it had no oil pressure; you put 20k miles on an engine with no oil pressure. I would call GM and thank them!either rebuild or swap it. the damage is already done. if you dont wanna spend more.... sell it.

[Frenchy]

Your engine is now a boat anchor. Thank you and please try again.

[bootlife]

I'm gonna say ur gauge is telling u stories, ur hearing the norm lifter tap that we all hear on those motors, ur smoke is prob cause its wore out ur u have a PVC issue. But I agree I'd be looking at a u-pull it for a new heart for ur ride.

[johngypsy]

well, i agree with you guys, but yea, i had bad oil in there for the past 10k miles, there is no knock, but it does have a tap, like rockers banging with no oil in there, tomorrow my mechanic will be doing a new sending unit, should of tried that first! but i will let you guys know of the out come on that!
the mechanic did also say the oil looked clean, but dirty, no metal shavings, but if the sending unit fails?
i will be installing a new motor next week,
but if you guys went threw the same issue? if you can please let me know, before i buy a newer motor,
thanks again,
john
houston tx,

[johngypsy]

thanks frenchy,
will do!

[fordkiller91]

Just get unit first try that another hard to take intake off and buy the speacial socket for and there y'all go.

[98silverbullet]

Take it to a GM service dept and have the cluster swept.
I replace 2 to 3 cluster in the 03-07 classic gmt800s a week.
Your cluster could be lieing to you.
If the cluster check out good then you have trash inside your oiling lines somewhere