I was a counterman--but not for the "zone"--yet!
I worked at 4 parts stores for nearly 20 years,2 small family type business ones and 2 large ones rivaling the local Napa's--its a very demanding job,though few customers seem to think so--I do agree that not all of todays "counterperson(s)" are the same caliber as us "old guys"--I know if you dont have a listing,they cant look it up right-and I think they are scared of lawsuits from "misapplication"selling you the "wrong" part at the "zone",when Napa seems to fear not,they just charge more...
If they do have the catolog,they dont refer to it very often,they just seem to rather not want to sell you that hard to look up,hard to get,and must be paid for in advance part with no cash refund ,you buy it,you own it type of sale,and say "Napa might have it" and let them deal with the hassle of special orders and non refundable parts sales.(and the resulting hard feelings between customer and the counterpersons,in the event the part does not fit or work for the customers needs--I HATED being in the middle in that scenario

)...
..They seem to want to sell the relatively "easy" to look up and get stuff--they do have good prices most of the time(at autozone) but it pays to still call everybody,I've found some of their prices a lot higher than even the dealership on some stuff!--Despite having a few good countermen and women at our local store,only a few that stayed there for more than 5 years(seems to be the burnout point for autoparts countermen--I left all the jobs I had after that amount of time!

)--
-Its hit or miss finding a good parts guy,especially the older guys that knew the older trucks the best,they are a dying breed-mostly due to high workload and low pay,and no health insurance in many stores,they quit and get better less stressful jobs-and they dont get any respect from their employers or the customers,its hard dealing with people on the phone and at the counter at the same time-
-And most if not every store I worked at always had a few workers who counted on the one person who knew his stuff to answer all their questions,(and take all the phone calls when the customers wont talk to the "dummies"),do most of their work,and then they get paid the same as or more than the counterman that did most all the work,while they "floated" through the week,the other guy takes the workload,thats fair,right??
-I cant bash autozone,cuz I might have to go to work there soon!--they are only a mile away,the pay is no worse than a "real" parts store,and they actually pay health benifits and other incentives--I made no more than 8 bucks an hour at all my jobs,up until 1994--I imagine you would probably get 12 an hour now if your lucky--still not much to live on at todays cost of living,VS what you have to know and do to get it.....I'd rather deliver parts than work the counter again--too much ulcer,not enough pay for me--its worth two bucks less an hour not to live on caffine and Tums all day,to me anyway--money aint everything ----

SORRY!--JOB RANTS OFF!!
I use 85W-140 in my transfer case and differentials,had no problems in cold weather or anything--if you use it in a SM465 you mught have trouble shifting it without gear clash in cold weather,and it will feel stiff until it warms up..thinner is better for the tranny,like 80w90--
85W-140 leaks slower too,if you have a "leaker"--I use some Lucas or STP in a few rears that were a little "loose" and it did quiet them down quite a bit,(and slowed the leakage down considerably)-- I think synthetic is probably the best choice,but the cost VS do you really need it THAT bad is debateable--like another poster said,for heavy duty,towing,high loads,use synthetic--an old daily driver with 100.000 + miles--regular 85W-140,or 80W-90 is plenty good enough--thats all GM put in at the factory,unless it needed the positraction additive stuff for a limited slip--why waste the cash?(unless you have it and dont care!

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