Good morning, I just found this site last night thought I would see if I could find an answer to a problem with my truck. It's a 2012 gmc, 5.3 motor, oil pressure is high 30's when warm , no mater temperatures or driving conditions until I hook onto a trailer. After about 250 miles my preasure starts to drop to low to mid 20 lbs. This during the winter towing snowmobile trailer weighing about 4600 lbs. Apparently the oil gets heated to the point it thins out. I've changed oil sending unit and screen. I've been using Mobil 1. I've talked to several techs that have no idea, just tell me to add some Lucas oils stabilizer. Any thoughts or advice is much appreciated. Thanks Tom
Oil preasure drop when towing
- Thread starter xcrtom
- Start date
No on the o ring and yes on the afm delete, I use a Range Technology device that plugs into the computer port. Is there a way to delete the afm by reprogramming computer?
This is why most vehicles no longer have an oil pressure gauge, or if they do, it's fake (Ford). The oil gets warmer when towing, so it'll have less resistance flowing through the engine, and you'll see lower pressure.
Technically, that's just disabling it, not deleting it. Delete would be removing the physical hardware for the AFM system.
I would run thicker oil if you are concerned with it. I run xW40 in my Expedition 5.4l 2v when towing and xW50 in my C1500 5.7l. Try 40 weight first and see how it does. If you want it thicker use Schaeffer Moly EP over Lucas
If you have a mechanic that tells you "just add some Lucas oil stabilizer" you need to find a new mechanic
My truck doesn’t give engine oil temp(at least that I have found), I am using Mobil 1 5w-30 decos. Oil pressure normally is around 55 lbs cold and around 35 to 38 lbs warm driving and 20 at idle. After towing my oil pressure will be 40 lbs cold and about 24-25 at highway speed, and that’s in 4th gear at about 2650 rpms and about 20 lbs at idle. After towing the oil pressure will stay at lower levels till I change oil telling me the oil is getting hot and breaking down, at least.
Unfortunately I’ve had 2 or 3 tell me to add the Lucas lol tells haven’t found the right mechanic.
What all is removed to delete? It seems what I’ve read the lifters are involved, what else?
your location + ambient temps are important as well as the miles on the engine as wear can lower oil pressures. unless its the mentioned O ring a xx w 40 might help + depending on your climate a higher cold # is generally an oil needing less viscosity improvers
How many miles? Clearances increase as the miles go up. I have 5W50 in my 6.0 with over 200K.
Texas Speed & Performance DOD / AFM Delete Kit for 5.3/6.0/6.2 Engines
DODdeleteKit DOD / AFM Delete Kit for 5.3/6.0/6.2 Engines
www.texas-speed.com
AZjeff
$50 Site Donor 2023
Did anyone catch this? He's using 5w-30 and towing a snowmobile trailer in the winter. AFM delete and new o-ring aren't going to change this.
GM 5.3l engines are not really known for fuel dilution especially given that it's not DI engine.