Finding Front Gear Ratio
#1
Finding Front Gear Ratio
Hey, my brothers bronco that I’m now inheriting due to my own truck being stolen has a junkyard rear end in it that doesn’t match the front, and I’m making him buy me a new rear end that matches so 4x4 is usable (and so the truck actually has decent power lol). Problem is, we don’t know if the front gears have ever been re-geared, and he wants me to be sure of what they are before buying a rear end (door sticker says 3.55’s). I don’t see any sticker on the front diff, and I highly doubt anyone would re-hear them, but I’m at a loss on trying to manually find a way to do the ratio. I tried every combo of diff locked and unlocked, different tires on and off the ground, and I cant get the front wheel(s) to spin with the driveshaft. Is it even possible to calculate it that way? I’m not super knowledgeable on how all the 4x4 and the diffs work and stuff so any help in finding the gear ratio is greatly appreciated, thank you!
#3
Does the truck have manual or auto front hubs?
With manual hubs simply turning the dial should lock it, with autos you may have to start by turning the front driveshaft to get them to lock.
If none of that works the hubs or diff are broken and you have more work to do... unfortunately.
With manual hubs simply turning the dial should lock it, with autos you may have to start by turning the front driveshaft to get them to lock.
If none of that works the hubs or diff are broken and you have more work to do... unfortunately.
#5
IF you do, with both front wheels off the ground and hubs locked, you should be able make the driveshaft turn and count it out.
#7
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#8
#9
Even if it is a 78/79, that requires draining the fluid. Not a bad idea if it's never been done, but probably easier to just rotate the driveshaft and tires.
Neutral would be useful if you were trying to count the rear diff.
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