Confused-'88 Dually????

[mar-tay1]

 Just picked up an 88 Chevy Silverado 3 + 3 dually. Now I know this site is 73-87, which is where my preference is, but it's the early body style as is my 1991 GMC Suburban 3/4 ton. But the other trucks changed in 88, right? So my questions would be: #1- are the suspensions the same as the earlier years such as 87? and #2-what would be the correct letter / number names for these two? C-3500 ? and V-2500? respectively. The PO lowered the Dually and I just need the front springs at the moment, and the internet is confused on which truck this is. ( pics of new and old bodies ) as well as mixed parts listings. Thanks!

[Jason S]

Welcome to the site.

The '88 to '91 Chevrolet/GMC crew cabs (3+3, Bonus Cab), some chassis cabs, Blazers and Suburbans were essentially the same as the '87-back.  There were some differences in these later year trucks from previous year trucks which don't really apply to your question. 

#1) From what you describe about your '88 dually, the suspension should be the same as the '87 R-30/R-3500. 

#2) Before 1987, C was for 2WD trucks and K was for 4WD trucks. Starting in 1987, R was for 2WD and V was for 4WD. In the 1980's. Chevrolet was using the 10-20-30 designations; GMC was using 1500-2500-3500 designations.  So a 1987 1/2 ton Chevy 4x4 is a V-10, while a 1-ton dually GMC would be a R-3500...

In 1988, the new body Chevrolet/GMC (the trucks without vent windows) were C or K series trucks, while the older body style (crew cabs, chassis cabs, Blazer and Suburban) were still R or V series trucks. 

So if your 1988 crew cab dually is 2WD, it would be R-30/R-3500 and if 4WD would be V-30/V-3500.   The 1991 Suburban, if 2WD would be a R-2500 and if 4WD would be a V-2500.

Hopefully this helps.
Others should post more or correct anything I got wrong.

There are some interesting things with these '80's/early 90's trucks. Post photos when you can.

[Irish_Alley]

i think everything stayed the same except for some had a different style mirrors up to 90 then the 1 tons got the 4l80e trans. but besides thats its the same thing but with electric speedo sensor for the 4l80e and the radio change idk when but my 91 doesnt have the 73-87 style radio