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Discussion Starter #1
Good afternoon gentlemen. My dad recently acquired a 1991 Silverado that has been in the family since new. Basic run down: Regular cab, longbed, 305, Auto, 4WD. 99K miles(no typo)

I will have the owner's manual soon, but I had a few questions...

What axles did GM use front and rear? How do I determine the gear ratio and if it has a posi? Will 75W-90 synthetic work well?

Dex/Merc in the tranmission?

Maxlife Dex/Merc in the transfer case?

Maxlife power steering fluid?

I will be using the grease gun, and replacing the PCV valve, air & fuel filter soon. Does the TBI system need any special attention? I'll get around to the ignition components.

Pardon the newb questions... I am familiar with blue ovals. Feel free to point out any other areas that need to be checked out. Thanks in advance!
 

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Welcome to the club. Besides the normal things like, fuel&air filters, cap, rotor, spark plugs (use A/C Delco's) fluid changes I'd take off the throttlebody and clean top and bottom with a soft toothbrush and throttlebody cleaner(don't use carb cleaner). Take the IAC valve out of the t/body and clean the pintle, they get carboned up with the t/body cleaner also.
 

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Welcome to the club Scott. Looks like the boys got you off to a good start.
 

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Good list to start, and some more pointers to follow. I would personally run full synthetic lube everywhere, including the engine.
 

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Discussion Starter #8 (Edited)
Thanks again guy. Much appreciated. Looks like it has 3.42 gears and no posi.

How do you advance the timing on the these trucks? The dizzy is kinda hard to see, and the 305 could use a little help. Will it take 2* of base timing on 87 octane?

Also, idk how accurate the odometer is, but my dad calulated 19 MPG on a 200 miles round trip, mosty back rounds and open roads. Pretty good, considering there is probably room for improvement. I'm impressed!

Edit: truck has stock 225/75/16 tires on it, which probably help with the milage although the look like passenger car tires haha.
 
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