Do i need a new diff ratio?

[6.2gmc]

Hi all i could do with some advice.I've only had the truck for about two weeks and it seems like the gearing is to tall.I know its a diesel but it seems very slow off the mark.It's running on 35"s and they were fitted here in the uk so i think they left the gearing stock? /forums/images/graemlins/1zhelp.gif

 

[Shaggy]

You're missing an important bit of information - what is the current diff ratio, and what was factory? Diesel Blazers were never very fast, but you should probably crack the diff covers to check the gearing, then compare that to the RPO codes in the glovebox to see what you have and what the truck had factory. That said, odds are that the gearing was too tall from the factory even with stock tires, since back then they geared these things for maximum economy with blatant disregard for performance. 35s with a diesel, 4.10s or 4.56s would likely serve you well.