urgent!!!! please help, daily driver rear end broke

[79 blazer]

so my blazer broke the pinion gear on the 12 bolt rear end, its going to be alot of money to fix it and resulting damage so i figure it will be cheeper to get a new rear axle and put it on myself. i hear from theese threads its pretty easy to find a 14 bolt for around 200 dollars, but i dont plan on going much bigger than the 35's i have, maybe 37's in a year or so. i need a solution as soon as possible, so any vendors with good deals or people trying to sell what i need i will buy it as soon as posible. so the question is,

1. does any one have a 12 bolt rear end with 4.10's or 4.56 in the northern colorado area for around $200 or less

2.do i need new spider gears and what not, or can i just get a new ring and pinion and a locker.

3. any ideas on where to go to get it fixed in fort collins/loveland cheap, and any other ideas would be apreciated.

 

[dyeager535]

If it broke once, theres your clue it's not strong enough for your usage.

You've got 2 choices, a 14SF or a 14FF.

I like the 14SF because of how I use my truck, plus the clearance, less weight than FF, and 6 lug.

I want to avoid getting stuck/breaking (again) as much as possible, a bit of ground clearance loss or weight increase is worth that to me. 14FF had too many downsides for MY usage.

Just my thoughts.

 

[79 blazer]

itb roke just from driving around town, and i thinkit was set up wrong plus there was when i had 3.73 in the front and 4.10 in the rear, oly used it like that in mud though, thank for the opinion.

 

[dyeager535]

Well, as you well know, just depends on how hard you are going to be on the truck. Pretty good sized tires for 12 bolts, but with sane driving they can hold up.

If yours broke due to improper setup, then no, I probably wouldn't consider the expense/hassle of going with another size rear axle unless you have to spend a bunch of money getting another one re-geared.

 

[coptezr]

If it broke once, theres your clue it's not strong enough for your usage.

You've got 2 choices, a 14SF or a 14FF.

I like the 14SF because of how I use my truck, plus the clearance, less weight than FF, and 6 lug.

I want to avoid getting stuck/breaking (again) as much as possible, a bit of ground clearance loss or weight increase is worth that to me. 14FF had too many downsides for MY usage.

Just my thoughts.

whats a 14sf in?

 

[dyeager535]

Started in '82, still in use I believe, ESSENTIALLY it's a 10 bolt that they made everything bigger on. 9.5" ring gear instead of 8.5", and lots of other small differences that add up to a stronger axle.

Look at "light" 3/4 tons and later ('88+ or so) "heavy" 1/2 tons.

Lots of 14FF and 14SF info on the board, I posted a fair amount of tech info on the 14SF not that long ago here.

 

[k20]

be aware though not all sf's are 6 lug. I have an 8lugger in the back of mine. After 88 there were 6 lugger sf's in the light duty 3/4tons. The HD 3/4's, I dont know if they got a 14ff or an 8 lug SF.

 

[mrk5]

Here in Greeley there's a u-pull-it yard called Anderson's. There are plenty of 14bFF and SF out there. Not sure what gear ratios are available. I'm 90% certain you can get one for less than $200.

Also check over at Colorado4x4.org

 

[79 blazer]

thnks alot guys anyone else have any help on getting a cheap replacement, or a area shop that has good rates?

 

[mountain4x4]

14 bff

I have a 14 bff w/ 4.10 gears, open carrier, from a '74 c20. It's just been sitting around, you can have it for $90 if you come and get it. I have a hoist to help it into your truck... If your front axle is 4.10, it's a cheap alternative. I was going to use it, but someone gave me a 14bsf for free, which is strong enough for me and my 285/75/16s (trying to save on gas), cheaper to rebuild, regear and buy an Eaton Posi for. Also lighter, better clearance, easier to replace brake pads on. Email me at [email protected] if youre interested. We just got about 16" of snow tonight, but it'll melt pretty quick. Lots of info on here about exactly what you will need to install it. I'll rebuild your 12 bolt for $175 + a great deal on parts if you don't want to hassle with the 14 bff swap (I'm SAE Certified, etc.)... Oh yeah, I'm in Nederland, just west of Boulder.

(However, after I have ordered all the parts from Randy's for my 14bsf, the outer pinion bearing race is STUCK in the housing. I tried heating the housing with an oxyacetalene, putting it in a shop press, using a large punch / sledgehammer, and cutting the race in half with a carbide bit on my die grinder, then using the sledge. NOTHING!. Now I'm afraid that even IF someone can get it out for me, the housing will be mushroomed out, and the new race will fit into the housing with too much clearance, and spin in it's seat... I also already spent the time to cut off the the spring/shock mounts, and contour the bottom so it doesn't catch on rocks as easy... Meanwhile my 10 bolt is about to explode.... Sorry for the hijack, but everyone is usually entertained by this kind of misfortune)

Has anyone jb welded a pinion bearing race into the housing? Is there any way to salvage this housing, or am I just SOL?

Dave

 

[Pookster]

What makes you think your 10b is about to expload?

 

[R72K5]

14ff with 4.10 for 90 bucks is a score and a half or two id be snagging it if i were you..

12 bolt with those gears woudl be non original and i bet you was set up incorrectly, very few ppl have the know how and tools to set up non removeable carrier gear sets and carriers

akso problem with 12 bolts was that the pinion nut comes loose on them and pinion goes kaboom

happens all the time ppl dont keep an eye on pinion nut and there goes the axle apart one day out of the blue

id go with a 14 bolt and preferably FF i see SF ones blow up all the time also

and the 88-up 10 bolts too, commonly break gears even just daily driver street only ones

its crazy..,


they are just crap

and ive only ever seen two 6 lug 14 SF's

are rare here,

all i ever see are 8 lug SF's

are the norm, over the SF 6's

like 99 to 1

also the SF 14';s started before 82

82 was the year that the 12 bolt ended, not the year that 14 SF began..


good luck

 

[dyeager535]

K30guy says (in previous post) that '81 was the first year for the 14SF.

I don't have my Hollanders handy, but what year do you think it first came out?

 

[mountain4x4]

My 10 bolt leaked out all the gear oil through the rhs wheel seal on a road trip at some point. Later, it started howling a little, so I took the diff cover off, and all the remaining gear oil was burnt. Upon removing the axleshaft, there is an 1/16 - 1/8" groove worn in the axleshaft where it rides on the wheel bearing, I replace the oil seal, and it is currently holding, but both axleshafts wobble on the shafts pretty good, and it still howls a little, even with full gear oil.

I actually just rebuilt a 12 bolt that failed due to the pinion nut backing off. You must use locktite and stake the threads on pinion nuts. Rebuilding 12 bolt rearends is really just like any other rearend, not sure what you mean about non-removable carriers/gears... I do prefer to use an aftermarket carrier (Eaton, etc.) on all 1/2 ton rearends as stock carriers are definately a weak point. Many people do have the know-how and tools to rebuild rearends, but most shops charge a small fortune around here...

I found another 14 bsf for my project down in Denver for 1/12 the price the junkyard wanted, so I'm feeling pretty lucky right now.

The most expensive part of installing that 14 bff I have, or any 8 lug axle, is , of course, buying 8 lug rims... The conversion u-joint is $25, $35 for u bolts, $40 for 32 lug nuts, and I'm sure a few other odds and ends...