No one tons for 1 reason
Frame hight.....1 ton trucks ran a taller frame then the 3/4 or 1/2. GM never did it for the Burb. The though was it would never carry the weight to justify making a one ton.
Course there are a few of us that will prove them wrong. I have carried 2200+lb of block retaining wall in my 88 a few times. When a E rated Michelin bulges with 70PSI in the tires...you might be a tad over the 8600 GVWR.
Few more facts on 73-91:
Only 4x4's got quad front shocks as far as I know. I know my 88 is a heavy R20 witha FF14 and a 454.
FF 14 was standard with the 454
No 454 4x4's
90 and 91 3/4's Thats the first two years of the 4L80e. Till I just read PsR's introduction post I didn't think any 3/4 burbs had OD till 90 but his buil sticker indicates his 85 has OD that probably is a 700R4. That seems to go along with the lighter duty 3/4. But his also shows the 4 shock 4x4 option.
V and R designations on 88-91 because of the new round bodies so GM could keep the C and K designations on the new body.
Reason that the Crew, Dually, Burb and K5 didn't change with the rest of the truck line in 88 is the Military. GM's Military contract for parts and trucks had not been fulfilled till 91. Rumor is the K30 while in Civilian market was not available in the old body the Military still got them through 91 is the "rumor". I have not been able to confirm but I watch the Gov sites to see if they ever show up.
Mile stone years on the 73-91
73-79 most 4x4 1/2 tons were equipped with full time 4x4.
all 80 4x4's had the NP 205 case
77 first year for gas door
80 first year for square headlights and only on about 20% that were built.
First major restyle was 81. Cowl separated from hood became fixed to the base of the windshield.
81 was also first year for the OD tranny TH700R4 Had some problems and a few ended up with TH350's
81 first year for 10 bolt rear in trucks.
73-77ish front axles in 4x4's was the Dana 44. The rest of the run ran the 10 bolt front that was also built by Dana as well as GM's plant. Look on the pig...you will find a Dana Diamond cast into the housing on some. Every thing knuckle out is interchangeable with a D44.
89 was another restyle year. Still used the same fenders but different core support and gill to get a grill styled like the new 88 trucks.
The restyle also carried over to the interior and got the new 4 spoke comfort grip steering wheel, Overhead console and updated seat covers (my Aunt works for TRW Johnson Control as a seamstress and sewed the seats for the design study's)
87 first year for FI
87-89 454 FI is highly sought after. Its a piggyback set up and will fit a Spread bore intake.
82 only year for front turn signals in the bumper. The rest of the run it was in the grill after or below the headlight before.
90 and 91 first two years for power mirrors.
I am sure I forgot a few things.
This will keep you busy. Site some folks I know did.
http://brochures.slosh.com/ Almost every GM Truck Brochure for 73-91. Also some stuff on the Chevy Chalet and GMC Casa Grande campers on the K5 platform for 76-77.
