Gear ratio? 72 C-10 fleet,LWB

[Ironangel]

Ive got the cover off my third member and there was no tag on the bolts. anyway to Identfy what the ratio is or what type of rear end it is? I know its not a posi,and the cover has twelve bolts. Thanks for your input!

[GruntMoanCough]

Count the number of teeth on the ring gear and divide it by the number of teeth on the pinion gear. Voila!

[LONGHAIR]

The tooth count numbers should be stamped into the edge of the ring gear.

41-10= 4.10
41-11= 3.73
41-12= 3.42
40-13= 3.08

[Ironangel]

Thank You Ron! I found a posi for $250, anything I need to know to install that thing? Will my standard axles work with a posi? Im new to truck restos so I Need all the help I can get! And again,Thank You! Michael. Thanks Longhair! Im a 51yr old Cherokee, my hairs long too! lol

[LONGHAIR]

As long as you intend to keep the same gears, changing to a Posi is not that bad. The biggest thing is that you absolutely must have a dail indicator to measure the backlash of the gears before you take it apart. You absloutely must put it back to this same number when the new carrier goes in. Do not mess with the pinion at all.

If you are wanting to change gear ratio at the same time, seek professional help....no seriously. Pay a pro and use new gears whenever changing ratio. It shouldn't cost you any extra to install the Posi unit at the same time.

Oh, and use a Synthetic gear lube in either case. It is cheap insurance.

[GruntMoanCough]

Originally Posted by LONGHAIR

The tooth count numbers should be stamped into the edge of the ring gear.

Oh, yeah.......... (old age creepin' in)

x2 - What the Longhair said about replacing it.

[Ironangel]

Originally Posted by gruntmoancough

oh, yeah.......... (old age creepin' in)

x2 - what the longhair said about replacing it.

lol! Thanks Man! PS. These pics are for you gmc-og, I might trade her for a decent Z1

[Ironangel]

Originally Posted by LONGHAIR

As long as you intend to keep the same gears, changing to a Posi is not that bad. The biggest thing is that you absolutely must have a dail indicator to measure the backlash of the gears before you take it apart. You absloutely must put it back to this same number when the new carrier goes in. Do not mess with the pinion at all.

If you are wanting to change gear ratio at the same time, seek professional help....no seriously. Pay a pro and use new gears whenever changing ratio. It shouldn't cost you any extra to install the Posi unit at the same time.

Oh, and use a Synthetic gear lube in either case. It is cheap insurance.

I will do as youve instructed and thanks for taking the time to give me details! This is my first truck resto and Im a little green, but I want to get her right! Thanks again brother!

[LONGHAIR]

No problem, that's why we're here....Good luck with it.

[Ironangel]

Ok,heres what I got.Its a 43-14, and I came up with 3.07.Is that a highway gear or what?Somebody tell me these pinion teeth marks are supposed to be there! There was an 1/8" play,in and out and left to right spin on the pinion shaft.The ring gear had a little slop in it too.Time to replace with new?Stupid question aint it LOL I just want somebody else say yeah man you need replace it!

[Jacfourteen]

yeah that can't be good! I'd say it's time for the works; seals, bearings, gears and carrier. If you swap the carrier you might as well find a posi or locker because it won't be any more work. You could always find a good used rear but that's a gamble too. And while you are changing things you should figure out what ratio will be best for you. The 3.08's you have are a highway gear. Let us know more what your plans are: engine, trans, tire size, usage, etc, etc. Good luck with it.

[LONGHAIR]

Yup that's bad....

You have a pinion bearing problem of some kind. I would say that the pinion nut is/was loose or the outer bearing is severely worn.
The pinion has shifted toward the centerline of the axle, hitting the carrier.
This is going to be on the higher end of repairs. You may be better off in finding another complete housing already loaded with the gear ratio you need.

[Ironangel]

Will do and and thanks Longhair Im about 90 miles north of A member that was going to pull a posi out of a truck for me, Ill see what he wants for whole rear axle. Bummer!