what is your opinion about the 12 bolt 4,56ratio axle in a lightweight vehicle
with 4cyl engine, sm465,np208 and 31"s

Thanks in advance

With a 4cyl and 31's you should never have a problem. Just stay away from the gov-lock. If you are going to abuse the truck you probubly should truss the housing...

Originally posted by fivos
what is your opinion about the 12 bolt 4,56ratio axle in a lightweight vehicle
with 4cyl engine, sm465,np208 and 31"s

Thanks in advance

i've got one sitting in my garage waiting to be tossed on my truck, just to get rid of that weak ass 10 bolt..
but i think it will do ok.. 4.10 gears and welded!

youll be fine and 10bolt and 12bolt are almost the exact same in strength

Originally posted by southern k5
youll be fine and 10bolt and 12bolt are almost the exact same in strength

I was just gonna say this.
What the 10 bolt lack in ring gear size more than compensates on the pinion size.
The 12b pinion is small so both have the same threashold of strength.
:D

i'll go tomorrow in the junkyard and check them out. Propably they are from millitary full size blazer. You know perhaps what ratio they use or there is something i have to check. what would be a fair price

If its truly from a military blazer 99% sure they are Front and Rear 10 bolts with 3.05 (I think that is the correct #... its 3.0?) gears and a rear gov-lock.

Probubly the worst rear full width axle chevy made.

Edit: Price...maybe 50$ if for some reason you realy wanted it, most people would sell them for scrap.

I'd consider a semi float 14bolt before I put a 12 bolt in. Much beefier but with about the same amount of ground clearance. You can get the semi float 14bolt in 6 and 8 lug versions.

Originally posted by J Bruce
I'd consider a semi float 14bolt before I put a 12 bolt in. Much beefier but with about the same amount of ground clearance. You can get the semi float 14bolt in 6 and 8 lug versions.

exactly what i was thinking. the 10 & 12 bolt are both c-clip and both about the same strength. I'm looking for a 14SF for my Z71 cuz i dont really wanna tow with the 10-bolt too much. For such a small rig though, fivos, I think it'll hold.

The 14boltSF is also a c-clip style axle. If that is all you are going to run, i would go with the 14sf. It is probably your best bet and for those times that you DO get into those binds you prolly wont break it where you would a twelve or ten bolt.

At last i have found 14 bolt axle and whatever axle i like here in Greece but the guy in the junkyard is propably the biggest, worst fucked up i've ever seen. He told me that he hasn't any axle except a pair of d30, amc20 from cj7 for 1200$ . One month ago i was there and he had show me a 10bolt and 12bolt and today he had nothing. what a fucker and of course he is going to take my balls

Just curious, how far away from a unimog 404 vehicle are you? Normally these vehicles from what i have seen, go for about 3 grand US$. It might be worth it for you to just use the portal axles off of one then sell the rest? just a suggestion if the guy is trying to sell you those axles for that much.

i beat the shit out of my 79 chevy with a 350 and 33's and it had a 12 bolt in the rear, open with 3.73 gears. never gave me any problems whatsoever.

lock it and put some real tires on it then beat it, and tell me you won't have any problems:rolleyes:

Originally posted by White Goat
lock it and put some real tires on it then beat it, and tell me you won't have any problems:rolleyes:


why don't you STFU? LOOK AT HIS POST!!! 4 cyl and 31's???? all i'm doing is explaining that with an 8 cylinder and 33's the 12 bolt held up fine.
Translation: I'm giving him reassurance that in his application, a 12 bolt should hold up.

Ive seen a welded 12 bolt break in a yota before, but it was on 33s. I dont like C clips axles so anything else I can tell you you probably dont wanna hear. In your case you should be fine;) Hey wanna buy a gov loc:flipoff2:

i had a 12 bolt with 33s and a 465 with the 400 and the rear end came apart on me when i pulled the cover the bolts in the spacer came out and tore every thing up. i have a 12 on mine but have full float 14 sitting waiting to go in as soon as the 12 goes

I have run a few 12bolt in my days. The first one I wasted the pinion bearings then it sucked the pinion into the case....bad situation. The next one held up fine....never broke a axle, even running 40's and a SB in a Blazer (although it was probably on its way). Now on my s-10 I ran a 12 in the rear for the past 3 years with a lock-right, 4.56's, and 35" tires. I was hard on it. I have a SB in it (only a 305) but in the rear of this light truck it held up great. I say go with the 12 if you want to keep your weight down. I should be fine in a light rig with 31's.

I would stay away from any type of ring gear spacer. In my old 12 bolt w/4.56 and a gov loc. It lasted about 400 miles then sheard every dam bolt from the carrier:nuke:

just my .02

I think it would be hard to break it with those small tires and a 4 popper. Mine lasted for years with 38's and a 350. I was easy on it though.