Verify gear size?= Project "X"

[Tbars4]

I need some help here guys...ok, the tranny is in and the truck is road legal....now to get her offroad ready...

Project X is a 91xlt 4x4 auto with the 4x4 button on the dash running on 35's...i pushed the button and no lite...since the stereo was taken out i reached in and found it was unplugged so i plugged it in and still no lite...after a warning by several members on the board i unplugged it...the warning was the previous owner may have re-geared the rear end as 4.56 and left the front axle as 3.73...my thinking was they unplugged it to look for the "Why isn't my truck 4x4 engaging" as asked so many times on here...as for asking the previous owner, he is the one who said the engine was blown, tranny 4x4 and a/c were perfect, so no, i can't ask him...

here is my question i need help with...how do you check and verify the rear and the front gears??? also, they used to put tags on the bolts, but sometimes they would stamp...is there anywhere else on the outside i should be looking for regear markings???

i would really like to throw this thing into 4x4 and see what she's got but i don't want to risk a kaboom after i just put a tranny in it, i don't want to re-do a t/c if i don't have to....thanks...

 

[IZwack]

You can get all the wheels up in the air, disconnect the drivesahfts from both differentials, and count how many rotations it takes for each pinion flange to turn the wheels in one axle one complete revolution. If it takes the same amount of rotation for both flanges to rotate the wheels one full revolution, then they are the same ratios.

 

[MountaineerGreen]

It should be stammped on the ring gear, but that would involve removing the diff cover. I don't know of any standard method for marking when regearing. I didn't tag anything when I regeared.

You can jack up the truck, rotate the tire one turn, count how many times the driveshaft goes around.

 

[Stic-o]

Spin the wheels!

jack up the rear and mark the pinion, count the amout or rotations of the pinion to make one full turn of the tire= gear ratio! :biggthump

should be able to lock the front hubs and do the same for the front

 

[MountaineerGreen]

Great minds think alike

 

[Tbars4]

thanks guys...i will be doing that this week at the latest...i just have to get a bigger jack for this truck, lmao....

 

[IZwack]

i just have to get a bigger jack for this truck

You dont need to -- you can hit the vehicle with the jack under the axle tubes. You dont need to go for the chassis.

Great minds think alike

Thats true .. but it takes an idiot to think beyond the norm:

 

[Tbars4]

I know, i was just joking as this truck is huge compared to my ranger...btw, take a look at my hub thread and see what the tire store gave me...

 

[Tbars4]

ok, i got it guys...with the help of rockranger's math...spin the wheel 2 times and count rotations of the pinion...thanks to froader and a couple others, the call was good and hopefully saved another major problem...i've got 4.56 in the rear and stock 3.73 in the front...i guess i should have to wait and swap the front gears in first to start working on the t/c... i will be posting a wanted add for 4.56's....