I recently acquired this Blazer($700, with an immaculate interior) for the winter driving and the prior owner ran STRAIGHT LUCAS in it!!! The engine is 4.3L and still runs strong. I did the normal stuff(plugs, cap, rotor, PCV[which was disgusting]air filter) and then did a seafoam treatment through the brake booster line. Man, you should've felt the Purolator oil filter that was on it with the Lucas...it must've weighed 6lbs.!!! I just put in Rotella T 15w-40 with a new Purolator PP. Should I stick with the Rotella or go to a 10-40, 20-50, or 10-30???
'91 S-10 Blazer 215,000 miles What Oil?
- Thread starter dwcopple
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I would wait and see if you have any consumption issues with the 15w40, then adjust your viscosity accordingly.
Straight Lucas eh? Man I thought that some of my concoctions were bizarre, but that is just downright CRIMINAL!!!
Straight Lucas eh? Man I thought that some of my concoctions were bizarre, but that is just downright CRIMINAL!!!
Sounds like a prime candidate for Auto-Rx. Even if you don't *think* it needs it, with that many miles it would be a good idea to do it. After that I think a good HM oil would be good, like Maxlife, or Castrol HM (which I've heard very good things about).
Triple_Se7en
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10w-30
Your 15W-40 is a bit thick for Michigan winters.
Your 15W-40 is a bit thick for Michigan winters.
A 10W-40 high mileage oil might be a good choice. I wonder how it even turned over with pure Lucas?
Hey eljefino it's called a compression tester.
When the OP puts "regular" oil in he's going to notice it burning somewhere. I bet. Though one can burn oil and still run fine if they keep up on the level.
The doohickie I speak of is an adaptor from plug hole threads to an air compressor quick-connect. One fills the cylinder with air so when the valve spring keepers are removed the valve doesn't fall into the cylinder; it's held up by air pressure. Then the spring is removed, seal replaced, installation is the reverse of removal. Though a compression test would be interesting at 210k with 100% lucas.
I did valve seals on my saturn SOHC, took an afternoon, $20 for the parts, and $3 for new RTV for the cam cover gasket. If that fixes my oil burning it will pay for itself in a case of oil at today's prices.
The doohickie I speak of is an adaptor from plug hole threads to an air compressor quick-connect. One fills the cylinder with air so when the valve spring keepers are removed the valve doesn't fall into the cylinder; it's held up by air pressure. Then the spring is removed, seal replaced, installation is the reverse of removal. Though a compression test would be interesting at 210k with 100% lucas.
I did valve seals on my saturn SOHC, took an afternoon, $20 for the parts, and $3 for new RTV for the cam cover gasket. If that fixes my oil burning it will pay for itself in a case of oil at today's prices.
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I concur that 5W40 Rotella would be a good choice. If you wanted to go cheaper, I'd just run 10W30 or 10W40 dino, probably Mobil 5000 or whatever namebrand is on sale. If you want to spend a bit more, I'd run 5W40 M1 T&SUV.
Personally, on a $700 truck, I think I'd just dump in 10W30 Mobil 5000, then add Valvoline Synpower if it burned/leaked/knocked with the 10W30.
I have a similar GMC with ~230,000, and I've fed it nearly every commericially availible oil at one time or another. The low revving, pushrod, TBI engines are pretty forgiving. I'd use the AC or Supertech filter, and just drive it into the ground if I were you.
Personally, on a $700 truck, I think I'd just dump in 10W30 Mobil 5000, then add Valvoline Synpower if it burned/leaked/knocked with the 10W30.
I have a similar GMC with ~230,000, and I've fed it nearly every commericially availible oil at one time or another. The low revving, pushrod, TBI engines are pretty forgiving. I'd use the AC or Supertech filter, and just drive it into the ground if I were you.
The Castrol High Mileage has worked very well at reducing blowby and consumption. Maybe try the 10W-30 (esp in very cold temps), and if that is an issue, the 10W-40 is quite thick, yet may allow decent cold starting. If it needs a different engine, one may be acquired from a salvage yard quite resonably. A brother-in-law had a very serious oil burning issue on a 91 S15 4.3L. He swapped the engines and paid ~$300 for one with 100,000miles and good compression. Even if you spent another $500 on the vehicle, it may give you a lot of transportation for the money, esp w/ 4WD in the winter! How are the trans, body etc? Good Luck!
trans is good, came with all service receipts including one for front and rear diff fluid change, transfer case fluid change and tranny fluid & filter change at 187,000 miles...I have recently changed 2 CV boots(torn) and the heater core was $200.00 to replace but worth it as I don't have the time or patience to do it right now...body is fair at best with typical Michigan rust and a poor repaint/job with new fenders that have slight paint sags on them!!! Interior is immaculate though...the buckets look like new!!! Digital dash is neat as well.
I have found that my 96 Blazer with a 4.3 likes a thinner oil. The Havoline 5W30 has been the most quiet of the oils I have tried so far,and a noticeable improvement in fuel economy. It has an HT/HS of 2.9., and Mobil 1 5W30 is 3.1. The GC and M1 T&SUV both have much higher HT/HS ratings and this engine did not like that. Food for thought!!!
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