diff ratio

[mayhem1982]

this may be a silly question but how do i tell what ratio a surf diff is on a truck that doesnt have the body tags on it?

[mudlva]

most accurate is to pull the head and count teeth

otherwise mark stud plate tdc on booth sides and pinion tdc

turn both stud plates simultaneously and count turns until the pinion does one full rotation then maths one what the ration is
quite easy for 4.1/1 but when you are getting 4.3-4.5-4.8 the areas can start getting a bit "greyer"

[mayhem1982]

so just found the tag in the glovebox

just done a search

its a g254

so am i correct that its a 8" 4.55?

[imsohi]

yea this is a 4.55 diff open 4 spider

[mayhem1982]

thanks