oil pressure?

[Tyler23]

i got a 93 1500 chevy pickup with the 350 and in the summer when the oil gets nice and warm the oil pressure drops fairly low. can i run like 15w-40 to give it somemore pressure? i got 10w-30 in it now.

[Shack]

When you say "drops fairly low" how low is it?

Do you hear any ticking/noise from the eng. when it does this?

If this is the case, it could be worn oil pump or worn rod bearing. How many miles on the engine?

[Tyler23]

well at idle its around 5-10. i know its to low and i should be looking at replacing it but it doesnt really pay to fix it as the truck is pretty old. the engine has 169,000 miles its had this oil pressure for about the last 15,000 and it still runs fine and doesnt burn any oil. the lifter tick when i first start it up for a sec but other than that it doesnt nock or anything. going down the road it holds about 25lbs of pressure. im just looking for something that may help this. when the oil is cold the engine pushs about 50lbs when its thicker. any suggestions?

[shizzy]

my old 94 K Blazer (350 as well) did just that with about the same liles on it. the engine held together till I sold it. I just developed a habit of resting my foot on the gas pedal. It seemed 100-200 RPMS made the oil pressure jump back up.at that age and miles I would just let it go unless you want to put a new engine in it. Run the thicker oil and hope for the best

[Whoaru99]

Is this pressure from the in-dash gauge?

Has it been confirmed with known accurate mechanical gauge?

[Jeremy airjer W]

I would like to know the answer that question as well.

[Tyler23]

it has that gauge but i wasnt sure at first if it was accurate so i put a napa gauge in it. so was it reads is true

[Shack]

Quote:

.at that age and miles I would just let it go unless you want to put a new engine in it. Run the thicker oil and hope for the best

Yep, I would just do the same with the info given above. If it does not sound like a box of rocks (tappets/lifters) at idle, when the oil pressure is very low, I would just go with it. That, or try shot gunning an oil pump at it to see if you can increase the oil pressure.

The chances of two gauges being way off and showing similar wrong readings is very rare.

Good luck!

[Tyler23]

ok well will the thicker oil help?

[Shack]

Sorry, but yes the 15w-40 should increase the oil pressure reading. How much? I do not know. If the low pressure is caused by a worn part, only time will tell how long said part will last no matter what oil you run.

Good luck!

[Tyler23]

ok well at around 120,000 my dad put a pump in it. i was told the bearings around probley just getting worn down? weather thats true or not idk. im mean it runs fine and all and i have driven it for a long time like this. will that lucas oil stuff do anything or is there any other product to try?

[Tyler23]

i hoping just to be able to get another 2 years out of it as then i will be done with college and be able to get something different. but now isnt the best time to have to put a motor in it.

[IFallsRon]

I'd have the pressure checked. I've replaced oil pressure sending units on Fords and Chevys.

[Bjjams]

I wouldn't trust those old guages. I owned 1 and my brother owns 3 early to mid 90's chevys and non have ever given a good pressure reading.

[Tyler23]

like i said before i alreadly have a different oil pressure gauge put in it. so im not going off the one in the dash. this gauge isnt a electrionic one it using the acutal oil from the engine to get its reading

[Whoaru99]

Thicker oil may help some as others have said.

I don't think I'd bother with additives.

Chevy engines, at least the good old small blocks, don't need a whole lot of oil pressure to stay together if you're not hot-rodding it.

If it's not rattling or knocking, I'd not sweat it too much.

[Tyler23]

ok that made me feel better. i thought if it had been like this for so long if it was going to blow up it would have a long time ago

[chanfish]

my 2002 yukon has had "cold start" knocks problems for over three years. starts up fine but soon as i pull out of the driveway she sounds kinda like a diesel. seen paul brand address this question awhile back--pushed product--seafoam or some kind of fuel additive--also my brother sent me a HSOforum where gm owners were reporting the same thing..my gm guy (walser) said not to worry about it...it goes away but still wonder what it is..have over 170k on her now..i know there must be other gm truck owners that have had this right?? any suggestions?

i didnt mean to jack this thread.. if i did then i am sorry...

[Jeremy airjer W]

There are two different noises that you can be hearing. If it is a hollow rattle type noise it is probably piston slap. Its literally the piston flopping around in the cylinder bore. There is no cure and there is no harm being done when this happens.

The other is a less frequent sharp tick or tap noise. This is typically hydraulic lifter related. It can be the result of a lifter or lifters bleeding down over night. Once oil starts circulating again in will pump them back up and the noise goes away. I have never had seafoam motor tune not take care of a hydraulic lifter noise and I have seen some dandies over the years. Half a can in the oil run it for 5-10 minutes or drive it up to a couple hundred miles then change the oil. Add the other half to the new oil.

[Tyler23]

yea ive never heard of sea foam fixing a lifer problem either. alot of the mechanics ive talked to said there nothing to worry about with that many vehicles do that but there owners dont always notice.

[fishorgolf]

My brother has a 5.3L that was using oil and he put a can of sea foam in the crankcase and oil use was almost eliminated after a couple months. He swears by it. Not sure if he was having lifter noise or not.

[michaelpettersen82]

I manage a quick lube and I will tell you that I STRONGLY reccomend that you do not use a 15w40 weight. You will end up doing more damage to your motor than good. I would recomend that you try a product called Restore, you can buy it at any parts store and I've seen it work wonders, it will increase your compresion and your oil pressure for sure. Running a 15w40 will just make harder for your oil pump to get oil to critical parts of your motor overall causing more problems than you have right now. Just my 2 cents.

[crothmeier]

My '93 Chev w/ 350 had low pressure when ibought it, 2 years later started knocking. Had to put a new oil pump in, and replace main bearings. It had 159,000 miles on it. That was 4 years ago. As far as i know that truck is still running today.

As far as the newer ones knocking on start-up, that seems pretty much common in the vortecs. I have a '97 chev now with 225,000 miles on it and doest use a DROP of oil in 3,000 miles. (knock on wood)

[Tyler23]

ok thanks for clearing that up for me. as for the seafoam in oil, doesnt that thin the oil out? doesnt seem like a good idea to me

[Jeremy airjer W]

I would recomend that you try a product called Restore, you can buy it at any parts store and I've seen it work wonders, it will increase your compresion and your oil pressure for sure.

I tried that once a long time ago when I was young and dumb. The crankshaft broke soon after pouring it in. Coincidence, maybe but if it claims to be a miracle in a can than its likely nothing more than snake oil! If you also notice how thick that stuff is its probably increasing oil viscosity! kinda like running 10w40 instead of 10w30?

Seafoam is designed to work in fuel, oil and other hydraulic systems (except brakes). As far as thinning the oil the amount of solvent in half a can Vs. the amount of oil then factor in the flash time of the solvent and its probably pretty negligible.