So I am probably going back to 10w-50 in about 1,500 miles as I have been using.
However it was suggested that 50 weight is too thick for a 95 K1500.
Has anybody been using a 50 weight oil for a exteded period of time with
any repercussions?
i.e. pump goin out, seals going bad etc etc?

 

Go with 50 wt in the summer and 40 wt in the winter.

we have mild weather all year round and I use 10w 40, but when my engine gets to about 75,000 miles (rebuilt engine)...I will probably go with the 50 wt. all year.

 

Ok thanks. Ya, I am at 150,000 miles myself (original engine).

 

I had a 1985 S-10 2.8Lt V-6 Blazer that had over 900K on it, one rebuild at 500K, 3 transmission later I sold it and it was still is going strong. I used Valvoline 20-50W and never had an oil issue with it. I strongly believe in Valvoline. And yes that is 900,000 miles.

 

I have so many older trucks in my roofing career, that I used 20w-50 in every one. They also had over 150,000 mile each

78 chevy suburban
85 s-10
78 chevy truck
72 dodge truck

 

Great, thanks for the replies guys.
That is what I am gonna do.

 

Hey the stock oil for that truck should be 5w30 40w is too much for that 5.7 what i would do is use either 5w30 or 10w30 and put a quart of Lucas oil stabilizer that should cure your problem with pressure and prevent dry starts

 

LOSTHYWY....I thought the idea for increasing your oil wt is so that the parts inside the engine stay coated with the thicker oil...which will reduce wear and tear on an engine when you started it....which already a 150,000 mile wear and tear?

 

10-30 is for newer and low mileage.
but with high mileage vehicles it is good to go to a heavier weight.

But I was thinkin about adding some marvel mystery oil or lucas oil
when I do the change. I was gonna add a quart of marvel mystery oil
last change but forgot.

 

Well if u have bearing wear then u would use heavier oil weight but if ur just trying to prevent engine wear then an additive like lucas or marvel is ok but keep in mind manufacture set the oil weight for bearing clearance on the crank and thru the oil passages by using a heavier weight oil u are going to blow sealsand possiibly cause blow by I have a 1996 yukon with 200k on it and iuse synthetic blend valvoline 5w30 just started adding lucas I still hold 40psi. At idle at 85degree summer day with a/c my pan is clean and I run 5000miles between changes I should get atleast 300k out of this engine no problem