Oil preasure drop when towing
- Thread starter xcrtom
- Start date
Well, he's the one that brought up the delete. And a new pickup tube o-ring absolutely can change and fix low oil pressure. It's also a decently semi-relatively not hard thing to change so it's a great idea and suggestion considering it's one of the top 3-5 things that fails on a GM 5.3l engine causing low oil pressure.
As far as the "oil thinning out" too fast and too much, there's just no way that the oil is doing that, especially in 250 miles, on a GM 5.3l engine.
What oil are you currently using?
I have been using Mobil 1 5-w30.
Would a UOA of the same oil before and after the "towing effect" be worthwhile?
Thats your issue.. you obviously have one of those unapproved SAE grades with 5-w30 that is almost as bad as 5-30 oil
/sarcasm aside. Oil doesnt perm. lose viscosity in 250miles of towing.. no matter what temp it reached.
So "something else" is clearly going on.
How many miles on the unit- and what pressure did it carry when new?
What RPM are you seeing mid 20's at? Never mind - I see all that now- thread moved fast.
mid 20's in the mid 2000's iso terrible using the 10LB per 1K rule of thumb.
Try a 40 grade and see what happens.
Sounds like you may have some clearance in the pump and or mains.
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I own a 5.3 and have towed my boat 4,200 lbs many times and have never had the OP’s issue. Also my 5.3 still has the factory engine management system program. My thoughts were based on his mention of program changes…
Did that include a fuel tune for more power?
Did that include a fuel tune for more power?
Are you getting this info from a scanner tool directly from the PCM or the dash gauge? I've found that the dash gauge isn't the most accurate when it comes to displaying the oil pressure, especially after 10+ years of age. It may only show 20 PSI on the gauge yet a scan tool will display 30 PSI as its getting the more accurate information from the PCM.
My brother's 97 K1500 the gauge are way off on just about everything as they probably all need to be rebuilt. Yet using my HP tuners VCM scanner everything is fine reading from the PCM.
I donot understand, 5w-30 is what it calls for. Specifically I have been using mobil1 5w-30 Merry going to try casteroil
I am getting it from the gauge on the dash and while what you say could be true the fact is my oil pressure is going down about 14 or 15 lbs after towing and it stays at lower levels till I change the oil.
Try M1 EP Hi Mileage 5w-30 . It's 11.8 vis vs. the 11.1 vis in M1 5w-30. Hope this helps.
How many vehicle's do you have at your compound?
GM LS engines seem to be known for fairly low oil pressure-I have a new Melling HV oil pump & pickup (to install) for the Express 6.0 in my sig, and it seems to have similar symptoms to the OP (although oil pressure does recover after sitting overnight & cooling off). I've been running the UPF48R & RGT 5W30, but I've been tempted to try some of my M1 Truck & SUV 5W40 to see if it makes a difference or not, even though it's not Dexos rated. The lowest I've seen towing/hauling in summer is ~20PSI hot idle in drive.
He was just being sarcastic. There's nothing wrong with Mobil 1
absolutely thats what /sarcasm means.
But unless his engine changes the laws of physics.
something else is going on.....
First step is to verify the low oil pressure, then if its actually an issue move on to mitigation or fixing.
I have numerous compounds where I keep my cars. If you're asking how many in total, in the 70's currently.