Does anyone know how i could figure out what gear ratio axels are that came out of a 1999.

 

There's probably a tag fastened to the differential cover that identifies what's inside, but that's not totally reliable.

You can count turns of the pinion versus turns of a wheel. If it's a limited-slip differential design, I suppose that you need to have both wheels free to turn and the ratio of pinion to wheel revolutions equals the gear ratio (I'm not experienced with these limited-slip designs actually behave, though). If it's an open differential, you need to keep one wheel from turning while you do your experiment. The other will then turn backwards and at twice the normal rate. For example, if it's an open differential with 4.10 gears, just over two turns of the pinion would result in one turn of the free wheel. For good accuracy, turn the pinion enough times to get several turns of the wheel and do the math.

 

lift the hood there is usually a tag that will say what gerar ratio you have

 

lifting the hood isn't an option anymore the truck was rolled and was sold for scrap iron. and i got the axels out of it and i need to figure out the ratio.

 

The rope trick as stated before works well. Tape a string to the yoke of the pinion and rotate the axle. 3.5 turns and its the 3.55, just over 4 turns, well 4.10.

 

I did the rope thing, and i found numbers on the pinion gear, The rope says 3:55 and after doing a little math the numbers on the inside say so to.

 

If you have access to the VIN #, get it and call the dealer. They can look up the truck in the computer and give you the "build sheet". It will have everything you need to know.

 

The nunber of teeth on the pinion and ring gear are usually stamped on the end of the pinion shaft that is threaded for the pinion nut, usually something like " 10 41 " meaning 10 teeth on the pinion, and 41 teeth on the ring gear, or a 4.10 ratio. Hope this helps. lol