what gear ratio do I have?????

[jetboat]

69 3/4 4x4 d60 rear (I think)

Any idea what ratio's came in these? my ID tag is pretty well gone and it would be nice to be able to put the right gear in the tranny. (or know what ratio to put in the front when I swap to disc)

[va_tlc]

it most likly will be a low gear, but if it were me id pull the cover and find the numbers on it or count the teeth and go that route, its hard to tell how many times that rear has been apart and where that tag came from, it be a shame to go by the tag and change your front to match or tear something up jus cause we went by the tag being the rite one,

[eedgell]

you can jack up the rear end[both tires], then carefully index one tire, and the pinion yoke. Rotate the tire one full revolution, carefully counting the number of revs the yoke makes. That number is your ratio. It is not exact, but will give you a real close idea.

[1969k10stepside]

I vote pull the cover off,get the numbers from the ring gear,and while you're at it you change the gear oil (probably needed it anyway) and the differential cover gasket.If you need to know 100% positive what the ratio is,you need to just do that and know the ratio and not estimate with the jack it up,spin the tire,and count method.Just my 2 cents.

[bhoeger70]

according to the Standard catalog of 4x4's by Robert Ackerson it has 4.55 in the front and 4.75 in the rear for the standard gear ratios.

[jetboat]

4.55 wow thats low but, I dont doubt it a bit.

Whats a good highway gear you can get for those axles??? I was thinking of going with something in the 3.55 range. I need fuel economy not stump pulling. Maybe I should just pull those axles out and put them in my offroad "creation" and just get a whole new matched "junkyard" set.

[va_tlc]

that probally be yr best bet, as far as gears that all depends on wat size tire u wanna run, in my case 72 3/4 had 4.55 front and rear, the ho52 rear i couldnt find a ring gear for, so i pulled the whole rear end and put a 14 bolt ff outa a 73 3/4 2wd truck, neighbor had it sittin in his back yard and told me as long as i put a rear end back under it i could have it, so i pulled the cover first to check gears an low and behold i struck gold 3.73 jus what i wanted with 33 inch tires, so just had to change my front ring gear. and thats all it took, yr not gonna be happy trying to run the hiway with 4.55 gears, hope this info helps, someone else will tell ya what all yrs rears will fit yrs plus the 14bolt will be so much easier finding parts for, hope this info help ya take care tony

[earl87gta]

My 68 had 4:56 front and 4:57 rear from the factory. I have a good gear calculator saved at home for 4x4s Ill post it here for you so you can play around with it to see what gears you need. for my tires 4:56s are about right for what I use the truck for but 5:13s wouldnt have hurt me to much.

[jetboat]

I was looking at new gear sets and 4.55 is about the highest gear I can find for the d60 with that particular carrier. I would be realy interested to see that gear calculator. When I check the junk yards around me they want a small fortune for 3/4 ton axles....makes me consider putting in 1/2ton stuff since Ill never be using this truck as a 3/4 ton or an offroad rig...just driving and hauling my quads around.

[Yukon Jack]

Are you sure you have a D60 rear axle? The Eaton rear axle is usually found in the 3/4 ton's. Here's a pic of the Eaton rear axle in my 69 3/4 ton



4.55/4.56 is a pretty common ratio for the 3/4 ton's.

[earl87gta]

this is the best 4x4 gear calculator i have seen http://www.grimmjeeper.com/gears.html

[jetboat]

Definatly not the eaton, I used an online "picture guide" and an old issue of 4wheel and offroad to determine it was a D60, havent found casting stamp yet...still cleaning the grease. If Im using that Gear calculator right, the gears in the axles are perfect..... I based it on 700r4 np208 35" tires....it says Ill be running 2057rpm at 65mph, seems good to me (tell me if Im wrong)