Here is what I know. 1984 3/4 ton GMC Suburban w/14 bolt rear. Engine is 454. I know that the ratio is either 3.73 or 4.10. I allready have 3.73 in my 10 bolt on my 87 K5. Also, the 14 bolt should just be a pop and swap. Right? anyways, the guy told me $150.00 bucks for the thing and if the ratio is 4.10 I should probably jump on it. Any help would be appreciated.