I have an '04 Blazer thats been great and want 100k more. I've always done my own basic routine maintenance w/ oil changes, air filters, PCV, throttle body cleaners, chassis lube and plugs and wires, tranny and coolant flushes. Going to do cap and rotor this weekend but what else? Was thinking about differentials, should I just check and top fluids or do a full drain? Also feels like a rougher idle than I'm used to but no codes recently so just wanna make sure I cover everything and keep her running strong.

 

If you don't know when the last time the diffs were serviced, I'd just pop the cover, clean/inspect, and refill with fresh 80w90 (or 75w90 synthetic).

The 4.3L v6 doesn't exactly have a smooth idle to begin with. I'm not sure I would worry about that unless it starts to become a problem. A lot of people have chased idle problems around and spent a lot of money in hopes of curing it while it was a barely noticeable "problem". If it isn't throwing codes that give you direction for diagnosis, you may be wasting a lot of time/money yourself.

 

Sounds good, thanks!

 

my bad idle was gettn worse so i changed the injector spider and no more missfire... but it still idles rough... yeah . im comin up on 100 k and i to have a bad idle. ive accepted this and realize its my blazer moulding itself to me... lots of noise from the rear and drinks alot