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fishrips
01-25-2007, 07:42 PM
Well the time has come to replace the rear diff on my 1/2 ton '76 chev. It's got a load of play in it, both on the driveshaft and axle sides. The brakes also need to be done. I was told by the previous owner of the truck that it has a "ratchet locker"... I havn't heard of that kind of locker before. I'm not a pro mechanic by any means, and I've never done a diff before, so I thought I'd run my ideas by ya'll.

1. I was thinking that if I could find an entire rear axle at a yard (pick&pull, etc..) with the same gear ratio I could just do an entire axle swap. Wondering if that is a good option. What do I look for to find an axle with the same gearing ratio. It would be great to find an axle with at least a limited slip, which I understand was a factory option. What is the price range for an entire axle from a junkyard as opposed to rebuilding the diff?

2. Could I swap out the 1/2 ton axle for a 3/4 ton? I'm running 35's right now and pull trailers, so the extra strength wouldn't hurt.

Thanks in advance!

In The Zone
01-25-2007, 07:48 PM
definatley look for a 6 lug semi float 14blt if that is what u got presuming it is a 6 lug pattern..

big up grade and will last the life of your truck

the ratchet locker per say is more likely a gov lok waiting to go boom...

u2slow
01-25-2007, 08:12 PM
the ratchet locker per say is more likely a gov lok waiting to go boom...

Not to mislead, but I've heard Detroits being referred to as ratchet lockers before. They do have some inherent slop in them too - which is normal.

The other 2 axles are definite upgrades. I'd probably run a Detroited 12b up to 35" tires if my truck came with one.

B
01-25-2007, 08:36 PM
definatley look for a 6 lug semi float 14blt if that is what u got presuming it is a 6 lug pattern..

big up grade and will last the life of your truck

the ratchet locker per say is more likely a gov lok waiting to go boom...
[stupid]


cheap reliable and bolts in ... is it a 4 wheel or 2 wheel drive ?

and get the gears u want for bigger tires ....

u2slow
01-25-2007, 08:39 PM
The 6-lug semi-float is not a bolt-in on a 87-older truck. The perches are a different spacing. I agree with it being a decent choice otherwise.

tenpack
01-25-2007, 09:25 PM
Its for wheeling or towing?

The natural urge is to say 14 bolt full floater because they are tough as nails 4x4'ing or towing, come in a slough of diff ratios ( 3.73/4.10 are common), can have 11 or 13'' drums( big brakes for towing) and are generally inexpensive.These have a 10.5'' ring gear.

the 14 bolt semi-floater is more like a 10 bolt axle( the one you have now) just beefed up. These have a 9.5'' ring gear, are c-clipped axles and are decently strong. These are available in 6 or 8 lug and. NOt too sure on diff ratios, but im assuming 3.73 and 4.10 are also common.

fishrips
01-25-2007, 09:35 PM
Thanks for the reply's. I've just checked the truck and it's got a 12bolt 6 lug. Not sure if it's full or half floating. I got the truck 2 years ago already built up., and I'm pretty sure it's not the stock axle the truck origionally came with. It got a spring over with 6" blocks. So a 14bolt 6 lug would be a bolt on?

It's a 4x4 (Would someone have 35's and a locker on a 2WD anyway??) so I'm wondering how to know what to look for to keep the diffs at the same gear ratio's.

I use the truck for mainly camping and a bit of fun in the mud, but not any serious wheeling. I 'm usually the guy the buddies call when they bury their stock trucks.

Thanks again for the reply's. I'm just learning about rear ends now, so use simple english... haha ;)

fishrips
01-25-2007, 09:41 PM
okey, to follow up that reply.... when someone says 12 or 14 bolt diff I assumed they meant the number of bolts on the diff cover... is that correct. I was doing some reading and the website was referring to the number of bolts on the axle end.

tenpack
01-25-2007, 10:47 PM
yup, number of bolts on the diff cover. the 10/12 bolt and 14 bolt semi-floater are all relitively rough, where as the 14 bolt full floater is shaped like a dana 70.

http://coloradok5.com/axleguide.shtml



that helps too.

fishrips
01-26-2007, 09:33 AM
Thanks for the reply's, everyone. I've done some reading and learned a ton. The only question I have left is... how do you identify the gear ratio of a rear end. Gotta get something with the same gearing as my front diff, or I'm gonna have a real short trip when I put er in 4x4... hehe. Vroom... BOOM!

Kinslayer
01-26-2007, 10:19 AM
Well, boom if you are on pavement, otherwise it's just a big chewy.


Look at the diff covers, they might have tags on them identifying the ratio.

Truckstuff
01-26-2007, 10:51 AM
Thanks for the reply's, everyone. I've done some reading and learned a ton. The only question I have left is... how do you identify the gear ratio of a rear end. Gotta get something with the same gearing as my front diff, or I'm gonna have a real short trip when I put er in 4x4... hehe. Vroom... BOOM!

Jack the truck up. Take the rear cover off. Spin the axle to find the numbers on the ring gear. Divide eg 41:11= 3.73


[cheers]

14Bolt 4.56
41851

MUD CHILD
01-26-2007, 11:09 AM
If you look on the ring gear usally it is stamped on there if it has 4.10's it would read 10 41 this means there are 10 teeth on the pinion and 41 on the ring gear. To get the gear ratio you divide driven(10) over drive(41) = 4.10, if you can not find the numbers on the ring gear, just count the number of teeth on the ring gear and divided it by the number of teeth on the pinion

Pudge
01-26-2007, 11:40 AM
if you have 3:73 gears I have a 14 bolt full floater located in Vernon you can have relatively cheap (it's my old man's).

Paul