'78 GMC Suburban V8 Fulltime 4WD Ambulance
 

Hi all you chevy folks!

I just became the owner of an old suburban. I am new to this, but want to replace a lot of parts (engine parts, alternator, brake calipers,tie rods... etc. etc.) I am looking for the best online resources and groups for folks talking about parts, repair and maintenance for this old thing. It is a 1978 15 (sometimes listed as "C-15") series Fulltime 4WD 1/2 ton Suburban (V8). I don't know if that means it is a GMC Sierra 1500, or what, but I would like to know. Motor is a 400-4 (~6.5 L). I am most immediately trying to figure out the exact specs for it -- the body has been stamped with "GMC series 15 Sierra", but the VIN indicates that it is a Chevy Suburban. I am also wondering where parts for these things are being manufactured nowadays. Would all parts be aftermarket if not from a junkyard? I have many other questions. This rig used to be an ambulance (has a modified hi-top)and it has two alternators, two batteries, a kill switch, a serious inverter/charger, and some other strange modifications, some are hooked up, some are not. I think only about 500 of these were made originally, but I have no idea how to go about getting a wiring schematic for it!! I also need the best and most comprehensive repair/maintenence shop manual available for this vehicle (for overhauling, teardown and rebuild) and I've only heard Chiltons... is there anything different or better or more specific to this kind of vehicle? Is this the right place to look for help? Any suggestions would be helpful. Thanks!

Re: '78 GMC Suburban V8 Fulltime 4WD Ambulance
 

welcome to the best source of info around!!!

First, for parts, there are several sources, a few being LMC Truck and Summit and others. Many times you can go to the local auto parts store or order online a Haynes or Chilton manual. The book you're looking for under Haynes says:
Chevrolet & GMC Pick-ups 1967 thru 1987 2WD and 4WD, also includes 1967 thru 1991 suburban, Blazer and Jimmy.

As parts for this could have been swapped out since the late 70s, the last time could have been with a GMC... but it doesn't matter if it is a GMC or Chevy, the parts are the exact same, the only difference is the decals. Especially since the Suburban carried both the Chevy and GMC name, the parts are interchangeable with similar year Chevy pickups, blazers, suburbans. In some cases the Suburbans were a few years behind the trucks, for example, in 1988 Chevy went to the new body style for the pickup trucks but the suburban did not follow this change until 1992.
Have fun with that burb!! the rest of us do!

Re: '78 GMC Suburban V8 Fulltime 4WD Ambulance
 

Ive recently joined the club as well lol