Thick oil wanted for 1991 4.3L GM V6

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1991 Chevrolet K1500, 4.3 V6. I want to run a thicker oil due to oil burning caused by bad valve guides. Truck is a beater but runs decent; gets me from point A to point B. Brand doesn’t matter. I didn’t have any success in finding a cheap 5W/40. Wondering if I should run a 10W/40 or just run 3 quarts 5W/30 and 2 quarts of 15W/40. Please advise.
 
For an oil burner-beater, use whatever you can physically pour in it. A conventional 10w40 would be my choice. If you have the combination you’ve mentioned, that will work great also. Are you certain it’s worn guides? Valve stem seals is typically the issue with the 4.3 and really inexpensive. Probably less expensive than 5 quarts of oil.
 
Yeah, after 5 or 6 years of owning it, I had the stem seals replaced but my mechanic said the valve guides were worn. Not really worth replacing. Roughly a $1500-$2000 vehicle. Just want to slow down the oil burning.
 
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Did he use just umbrella type seals or a combination of factory o-ring and umbrellas? If just either it won’t stop the oil consumption. We had a fleet of them back in the early nineties.
 
If the vehicle were mine, I'd try any cheap 15W-40 and see how it improves things. Sure, most 15W-40 are diesel oils, but it won't make any difference in your (old) gas engine.
 
1991 Chevrolet K1500, 4.3 V6. I want to run a thicker oil due to oil burning caused by bad valve guides. Truck is a beater but runs decent; gets me from point A to point B. Brand doesn’t matter. I didn’t have any success in finding a cheap 5W/40. Wondering if I should run a 10W/40 or just run 3 quarts 5W/30 and 2 quarts of 15W/40. Please advise.
Start with 10W40 with a jug of 15W40 for top up’s - if that slows the consumption you could run 15W40 in the summer …
 
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I didn’t have any success in finding a cheap 5W/40.
Would this be to expensive?

$22.97 per 5 quart jug. It used to be $18.97, but inflation happened. It uses GTL base stock, so it's actually really high quality oil.

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It's still February in South Dakota... I'd stick to a 5W-30 for the next few months. Once the cold nights have passed then give the 10W/15W-40 a try.

I used to run 10W-40 in a Honda Accord when Iived in Wyoming and those cold winter starts were brutal.
 
I'd skip the Euro 40s they are on the thin side. Like others...HD 15W40.
 
Starting temps is the main concern when choosing an oil the XW part, South Dakota winters can get a bit brisk. The 4.3 is a good engine try a 15W-40 for the summer. Thicker oil may or may not help but it is fine for use when the starting temps are a match for the Wratings..
 
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Asking for oil recommendations always makes for lengthy and interesting threads. (y);)
 
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1991 Chevrolet K1500, 4.3 V6. I want to run a thicker oil due to oil burning caused by bad valve guides. Truck is a beater but runs decent; gets me from point A to point B. Brand doesn’t matter. I didn’t have any success in finding a cheap 5W/40. Wondering if I should run a 10W/40 or just run 3 quarts 5W/30 and 2 quarts of 15W/40. Please advise.
How much oil do you burn in 1000 Miles of Driving?
 
@otis24 I'd consider running HDEO 5W40 since you are in South Dakota. You could do a mix of 5w40 and 15w40 if you think the oil burning happens on start up or when the engine is cold... Blain's F&F has some good choices and the store brand is decent oil. I use their 5W40 in all my OPE.


Just my $0.02
 
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