20W-50 anyone?

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I've used 20W-50 Pennzoil in a Merc Tracer (basically a rebadged, and slightly rounded Mazda 323). That manual recommended 10W-40 for year round operation and 15W-40 or 20W-50 for hot summer climates.

The only problems I had were not changing it often enough.:) (Not a good idea to run 20W-50 with 8000+ miles on it in a Buffalo, NY winter.:(, I suspect the engine died a slow death as a result...
 
I use 20W-50 in my twin merc 8.1S inboard engines in a Sea Ray 340 Sundancer instead if the MErc 25W-40 oil speced for them.
 
Can still get Synpower 20w50 (PAO) two for price of one at Adv Auto through end of this month. Comes out to about $2.74 each.
 
I had an 85 Mazda GLC and then my present 88 323 - I remember the "made for high reving engines" slogan - thus I was a Castrol 20w50 user till I finally went to Amsoil in the mid 90's. Recently put ST (dino) 20w50 in the 323 just for giggles and to see where I stood w/o HMs for one OCI - the engine had a noticeably heavy sluggish feel. No plans to go back to it.
 
20W-50 is a recomended weight for above freezing temps in every older Benz or BMW. I've used it in both, usually GTX. I also use it in small engines calling for a straight 30. Seems fine.
 
Using 20w50 in a KX250F MX bike. No issues so far. The factory recommends a 5w40. The heavier oils hold up better with the shared sump/gearbox. I also add 1 quart of 20w50 to 5 10w30's when I service my neighbors Jeep. I have read that the straight 6's like a slightly thicker oil. And, I add 1 quart of M1 15w50 to 4 Mobil HM conventional 10w30 in a 350 SBC I service. This Chevy is a full time work vehicle towing a 3 horse trailer, or hauling feed for said horses. That SBC has 157,000 on it and runs very well, with no leaks, consumption, or pressure issues. 20w50 still has it's place in a thin society. There ought to be one of those "Big Daddy" t-shirts made with a quart of 20w50 printed on the back.
 
I used to use Duckhams Q 20-50 in my '64 Mini back in England in the '60's. The engine survived an unnoticed water hose blow out at high speed through the back twisties (say 70 to 90 mph). I finally noticed the smoke from the block paint crisping from the heat and stopped. Replaced the hose and the coolant (not the oil) and carried on. Lasted another 40,000 miles, 'til the gearbox died, anyway.
 
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I was just wondering if anyone is using 20w-50 right now or in the past. What vehicle/engine did you use it in? Will a 20W-50 hold it's viscosity at all or will it shear as bad as a 10W-40?

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I used to use it in my 69 firebird and it blew the engine. Never again. New rebuild held up.
 
The 20w-50 was a popular oil here in the late 70's, 80' and early 90's. I could never understand why anyone would use a 5w-30 in this climate which the manual stated in those years especially the V-8's. The 20w-50 had far greater protection.
The oil still sells well here.

I used a 30w, 40w and 20w-50 on a 1988 Toyota Corolla with no problem. That engine ran hot!
 
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20W50 did not blow your engine. You had other problems. Australia wouldn't have many vehicles on the road if 20W50 caused problems.

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Your comment cannot be confirmed or denied. It was 1 bearing and my engine builder stated not to use that wt. But I know using the lighter oils gave more power with no problems.
 
I started a thread on using RLI 15w-50 to control oil consumption and smoking. I like the idea of using the correct weight in an high mileage engine to control oil consumption and not adding thickeners to something like a 10w-40. It appears that there is something to the oil composition to stop oil consumption. I have had immediate positive results. More miles are needed but besides a 100+ mile trip Friday in 98F+ temps, today yesterday and today I made a trip from San Diego to Phoenix and back in 110F+ with this oil in the crankcase, a/c all the way and speeds around 70-80mph across the desert and up and down the mountains, 900 miles in total and it looks like I burned 4 ounces of oil, in a car that would have burned at least two quarts or more for the same trip. In their place 50 weight oils are good stuff.
 
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I use 20W-50 in my twin merc 8.1S inboard engines in a Sea Ray 340 Sundancer instead if the MErc 25W-40 oil speced for them.

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I'd stick with the Mercruiser stuff (since it has no viscosity improvers) or go with a synthetic. The 20w-50 used in my Land Rover Discover sheared to a low 40 weight in a little over 3000 miles. Also, other marine engine builders that use the 8.1 block spec straight 40 for some reason. The small block gets a 15w-40 recommendation.
 
I would use the 25w-70 or even the 40w-70 on those heavy loaders rather a 60w. There are no 70w here. It wouldn't be a problem!
 
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