96 K1500 - low oil pressure

[98_k1500]

That should work, I forgot, I was gonna look at mine on my lunch break and see if that plug on the front of the block is accessible.... Only problem is i walked outside and my motorcycle is sittin in my parking spot lol... I have no idea what type of adapter you will need or if a regular manual gauge has one with it or not.. Probably just have to pull it out and see

 

[great white]

Sorry to say if you do actually only have 5-6 psi at idle it's going to need work fairly soon. Getting a mechanical gauge on it first to verify it actually is low pressure is a good move.

Low pressure like that is usually main bearings.

Any chance the PO had a receipt to prove it's a 30,000 mile engine or was it just his word?

It could be a fairly new engine and still have low oil pressure if they messed up and got antifreeze in the crankcase.

Do you know if it's a new longblock or a shortblock replacement?

Longblock is less likley to have been messed up this way. Shortblock is a much higher possibility of having the mains wiped out by careless work....

 

[magimerlin]

And a note about high volume oil pumps...... on a street driven vehicle you will suck the oil pan dry before the oil recirculated back to the pan.... In 90% of applications as I am sure someone will chime in and says it work fine on there's. Bottom line is a hv pump will not solve bearing issues or other mechanical issues if there....it will just make them worse...

Take a good look at your sensor as well as it could be bad.....

sent from what use to be a great country..

 

[edc5302]

Thanks for all the great replies and advice.

The PO did not have any paperwork on the new motor which makes it suspect. He did say it was a new motor not a rebuilt motor. The transmission was also new and was done at the same time.

He told me about the low pressure and said he had someone check it manually and it was at 15 psi at idel. I have a manual guague and will verify myself this weekend (hopefully from the oil filter housing and not from the sensor)

I did change the sensor and it did improve the guage reading especially at start up.

I hope it's not bearings, but if it is I'll just repower.

Again, I reallly appreciate all the great advice. Ya'll are great.

 

[98_k1500]

Be sure to let us know what you find

 

[great white]

Thanks for all the great replies and advice.

The PO did not have any paperwork on the new motor which makes it suspect. He did say it was a new motor not a rebuilt motor. The transmission was also new and was done at the same time.

He told me about the low pressure and said he had someone check it manually and it was at 15 psi at idel. I have a manual guague and will verify myself this weekend (hopefully from the oil filter housing and not from the sensor)

I did change the sensor and it did improve the guage reading especially at start up.

I hope it's not bearings, but if it is I'll just repower.

Again, I reallly appreciate all the great advice. Ya'll are great.

Even 15 psi at idle on a 30,000 mile engine isn't great.

A new engine would be something like a GM crate deal. They sell new replacements as well as performance packages.

As an example, my 6.5 diesel is new right from GM. It runs at 35-40 psi hot by 1500 rpm and will drop to 25-30 psi at hot idle (675 rpm).

Gassers are a little different, but getting around 10 psi at idle is pretty low. IIRC, the oil pressure idiot light is triggered at 8 psi.

I'm thinking the PO might have told you a little fib or something happened to it between install and sale....makes that "new" transmission suspect as well.

Not the most cheery news, but there it is.....

 

[edc5302]

Yes, I agree the PO may not have been completely straight with me, but I traded him even for a 6 cyl, 99 mustang with over 2000,000 miles. Even if I have to repower I think I'be OK on the deal.

I'll know more when I check the pressure manually this weekend.

thanks again for everyone's responses

 

[IOWNJUNK]

Yes, I agree the PO may not have been completely straight with me, but I traded him even for a 6 cyl, 99 mustang with over 2000,000 miles. Even if I have to repower I think I'be OK on the deal.

I'll know more when I check the pressure manually this weekend.

thanks again for everyone's responses

Sweet. Didnt know ford made a car that could run 2 million miles.

 

[edc5302]

Checked the pressure mannually using one of the fittings on the oil filter housing. Much easier than the oil pressure sensor. It appears these may be for a oil cooler.
Bad news is the pressure manually was the same as the pressure on the guage.

Changed the oil and filter. Went with 10w 40 and reread pressure both manually and on inside guage. There was a little improvement, but the pressure is still low.

My next step will be to install a high flow oil pump. I will post my results

 

[great white]

I would suggest you bite the bullet and check the oil pressure at the oil sensing port before throwing hard parts at the engine.

Cooler ports are likely no the same as the pressure taken off the oil gallery.

It's a "no cost" check except for your time.

If your pressure actually is low, a high pressure oil pump is not the fix. The fix is likely new main bearings or rod bearings.

The other possibility is the oil pump bypass spring (controls pressure) is buggered or the pump itself is toast.

Checking the pump is easy, you just pull the plate off and do some clearance checks on the rotors. Ya gotta pull it out of the block to do it, but if it checks out good you will know changing it would just be throwing good money after bad....