5w-20 in GM 5.3

[Triple_Se7en]

Originally Posted By: Stewart Fan
I've got two changes worth of 5w-20,left over from my Wrangler. I sold the Wrangler and don't know anyone with a car that needs 5w-20.

GM recommends 5w-30 in my '07 Tahoe. Any issues running a 5000 mile OCI with the 5w-20? Or should I just rely on the OLM and run it out to 6000-6500 like the OLM normally says to?

The oil in question is PYB and M1


Check your magnetic drain plug for shavings attached to it. Mine was smothered in metal shavings using 5W-20. I switched back to 5W-30 and no shavings.

 

[gfh77665]

Originally Posted By: Triple_Se7en

Check your magnetic drain plug for shavings attached to it. Mine was smothered in metal shavings using 5W-20. I switched back to 5W-30 and no shavings.


Uh oh! The uber-intelligent "thin guys" are gonna have a stroke!

Be prepared to be flamed unmercifully by them soon!

 

[CATERHAM]

The technical answer which no one has directly addressed is oil pressure.

As long as you maintain at least the minimum OP that's spec'd for your engine you can run the lightest fully formulated oil you can get your hands on.
A typical 5W-20 (HTHS 2.6cP) is thicker than necessary every time you start the engine cold until the oil temp's get up to at least 90C. Since you don't likely have an OP gauge or oil temp' gauge you'll have to make some assumptions as to how you drive your truck. The first half hour of running, even in the summer is no problem. Driving in the winter generally won't get the oil hot enough.
If you run the 5W-20 in the summer, simply avoid full throttle on the hottest days after half an hour or so of running the engine and you should still maintain an adequate safety margin.

 

[dave1251]

Originally Posted By: CATERHAM
The technical answer which no one has directly addressed is oil pressure.

As long as you maintain at least the minimum OP that's spec'd for your engine you can run the lightest fully formulated oil you can get your hands on.
A typical 5W-20 (HTHS 2.6cP) is thicker than necessary every time you start the engine cold until the oil temp's get up to at least 90C. Since you don't likely have an OP gauge or oil temp' gauge you'll have to make some assumptions as to how you drive your truck. The first half hour of running, even in the summer is no problem. Driving in the winter generally won't get the oil hot enough.
If you run the 5W-20 in the summer, simply avoid full throttle on the hottest days after half an hour or so of running the engine and you should still maintain an adequate safety margin.


This is the most logical response that I have seen yet. You can use 5W-20 for an OCI you will not have a problem. I do not see you taking you Tahoe to the dragstrip. It is true GM pushrod V8 seem to run smoother on a thicker oil but I have seen there is no additional wear caused by using a lighter oil.

 

[Superbuick96]

Return it to wally wether you bought it there or not, they'll give you store credit w/o a reciept.

 

[wolfc70]

When I had my 2000 Saturn LS1 with the 2.2 Ecotec, I accidentally bought a case of Havoline 5w-20. I did not even notice it until a day after the change, I looked at the remaining quarts on the shelf and noticed the 5w-20. My car did not notice at all. Ran 3 changes with that oil and could not tell a difference over 5w-30. As long as you are not using the engine hard, I do not foresee any issues based on my experiences.

 

[daman]

for what it's worth i have ST 5w20 in my old '85 350 Chevy plow truck and yep the bearings are still in it. If your not doing any heavy towing or seeing high oil temps I'd use it sure also be a good winter/cool weather oil for you.

 

[tflessner]

+1 on that idea. I've done that also. Exchange it for the proper weight oil.