Valvoline max life oil.

[Ben Lamberson]

Just wondering if anybody has used this or recommends it. I have an '86
4000csq with 174,000 miles. I'm currently using castrol syntec 5w-50.
This is what the local dealer recommended. The previous owner was using
mobil 1 full syn. not sure which weight but the one with the green cap.
My car has been using about 1 qt every 600 miles. Will max life help? or
is a different syn oil better? or different weight? I am in Wyoming so
the car is going to see some very cold weather- does this effect the oil
weight choice?
Thanks for any advice.
Ben