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14 bolt in my '87, what is needed?

Discussion in 'The Garage' started by chev4life, Jan 5, 2004.

  1. chev4life

    chev4life 1/2 ton status

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    14 bolt in my \'87, what is needed?

    Just like it says, I really need gears in my '87 and figure since I am here I might as well go with the 14bolt FF. First off, I found one that is already inspected and done over with 79k on it factory 4.56's and gov-lok...is this worth $670 shipped with the spring perches moved? If so, what else will I need to complete this job? I know about the u-joint and springs pads/u-bolts. What do I need to get the ebrake, brakes setup, and is it safe to use an 8-6 lug adapter so I can stay with my current rims?
    Last off...do I really need the 14 bolt? I might go with 35's, but unsure yet, and I currently have 33's, i wheel hard 3-4 times a year, go camping and to the snow many times and usually just cruise and tow my 16 foot boat. Is the 14 bolt over kill, should I just throw in some 4.56's and do the same in the front and live with it? It is going to cost me a good 500-600 more to get the 14 and 10 front setup than doing just gears all around. Sorry for the long question, but I would really appreciate some good answers.
     
  2. one ton burb

    one ton burb 1/2 ton status

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    Re: 14 bolt in my \'87, what is needed?

    well if the 14 bolt is out of 1981 and older you will need the backing plates off of a 14 bolt semi floater. and to run a 8-6 lug adapter the hubs will have to be turned down in a lathe first, i'm not sure how strong or safe a 8-6 lug adapter is but for you it mit just be better to find a 14 bolt semi floater with the 6 stud axles shafts
     
  3. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

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    Re: 14 bolt in my \'87, what is needed?

    Well having a 14BFF is all about preferance if it isn't needed, like me, I'm only running 35x16 boggers and I would probably be just fine with a 14SF but I just prefered the full floating axles, bigger better ring gear and gov-lok, bigger brakes, and they are plain stout cool looking rearends. If you wan't to stay 6 lug than I would look for a 6 lug 14BSF if you can find one otherwise a FF with the 8 to 6 adapter.

    $670 is a lot for a 14BFF, A 4.56 locked rearend like that would go for 200 to 250 around here. You could probably find one at a local wrecking yard. Don't be affraid at all of the 14FF gov-lok because they are decent in the FF and if you are towing and in snowy conditions a detroit isn't for you.
    I wouldn't regear your 1/2 ton stuff because it is more expensive than getting different axles and they would still be 10 bolts. I wouldn't go with 4.56's if you stay with 33's, that is a bit low but is good for 35's. 4.10's would be better for 33's and decent for 35's.
    I would say get the FF because that axle is one of the best light truck rearends ever produced IMHO. /forums/images/graemlins/thumb.gif
     
  4. CHEVY 4WD

    CHEVY 4WD 1/2 ton status

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    Re: 14 bolt in my \'87, what is needed?

    I agree with rjfguitar its nice to know you have the FF so you not worried about blowing it out... but $670 /forums/images/graemlins/eek.gifthats alot of $$$ I wouldent look to buy a non-local rear end there TOO heavy to ship
     
  5. chev4life

    chev4life 1/2 ton status

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    Re: 14 bolt in my \'87, what is needed?

    I have found a few beat up ones around that are local and cheap, but I would have to fully rebuild them. Is that tough with the 14 bolt, or even worth it? Figure 350 or so for gears and bearings and then another 500 for a posi. If I go with the 14bolt I also want the strength of the FF and would use the 8-6 lug adapters until I get a chance to upgrade the front and go with 8 lug wheels all around. Since my rear already has a new auburn posi in it I can get gears and bearings setup and installed for $490...i dont think I could come close to that in building a posi 14 bolt, am I wrong on this?
     
  6. CHEVY 4WD

    CHEVY 4WD 1/2 ton status

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    Re: 14 bolt in my \'87, what is needed?

    you may want to do a little more research on the 14bolt FF before you deside on anything(use SEARCH)... as far as "posi" you have 3 options 1 -Detroit Locker(uses stock open carrier) runs about $350+- 2 -ARB(complete carrier replacement) there really expensinve and your gonna need some type of air supply 3 - Factory Gov-Loc there not the greatest thing out there but in the 14bolt FF they hold up pretty nicely(im running one right now)
    ok now for the FF/SF
    Im not sure if you know this or not but the 14bolt FF and 14bolt SF are COMPLETELY differnt diffent rear ends with the main thing in common being the number of bolts in the Diff cover.
    1 last thing I did the swap in my truck too, I went though the same thing tryen to find parts with out breaken the bank but give it time and look at every possible way of getting the rear end you want, If you have the room you can probably pick up a beat up parts truck and use the axles our of that... you can some times re-use some of the bearing just inspect them you might wanna change the hub bearings and races though just because its easy /forums/images/graemlins/thumb.gif
     
  7. 87BrnRsd

    87BrnRsd 1/2 ton status

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    Re: 14 bolt in my \'87, what is needed?

    $670 for a 14ff is way too much. I got my 14ff brand spankin new 0 miles with 4.56's and a detroit locker for $550. If I were you, I would look for another 14ff. If you plan on running 35's one day, then you definitely want to go ahead and get the 14ff. If you dont, and one day you do decide to go bigger, you will be kicking yourself. Also, if you do hard wheeling, even 3 or 4 times a year, with a 10 bolt and 35's, chances are its going to break. My friend had a blazer with a 10 bolt rear and 35's, and the axleshaft snapped just crossing a 2-3 foot deep ditch in the parking lot at my school. The tire came off when he was going about 40mph down the road. /forums/images/graemlins/eek.gif Putting the 14ff in you blazer will be easy. The e-brake wont hook up, dont know how to get it hooked up so I cant help you there. Other than that, if its from a 1 ton, each perch is going to have to be moved out 1 inch, and the shock mounts will have to be flipped. If you can find a 14ff from a 3/4 ton it will bolt right in. Aside from that, you need either a conversion u-joint (pricey if you go through u-joints somewhat regularly), or you can have a driveshaft shop change the end of your shaft to the 1350 style, and you can use a regular 14ff u-joint (probably wouldnt cost more than about $50 at a respectable driveline shop, and $50 is less than the cost of 2 conversion u-joints.) Other than that, if you have basic skills, you and a friend should have your old 10 bolt out, and the 14ff in and ready to ride in about 4 hours. All you have to unhook is the u-joint, brake lines, u-bolts, and shocks. None of which should be hard. Same on the installation. Let us know if you need any more questions answered.
    -Harrison
     
  8. chev4life

    chev4life 1/2 ton status

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    Re: 14 bolt in my \'87, what is needed?

    Hey, thanks for the help guys I really appreciate everything (I love this forum) I was thinking a little about the 14bolt SF and actually think that would be better for what I am planning on doing. 35's, maybe 36's would be the biggest I would ever go so I shoudnt have to worry about it and no I am not going to pay 670 for the FF. 87BrnRsd mentioned a new 14 locked with 4.56's fro 550....if I saw that I would buy it in a heart beat. But the prob I dont see any local 3/4 ton 14's which would make everything easy as pie from what I understand. What should I expect to pay for one I can just drop in with no hassel with 4.56's and detroit posi or gov-lock?? I am still new to this whole change over and really dont want to get ripped off. Anyone in the general bay area know of any I can get? A little driving wont botther me if I can get what I need. Oh, thanks again.
     
  9. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

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    Re: 14 bolt in my \'87, what is needed?

    [ QUOTE ]
    What should I expect to pay for one I can just drop in with no hassel with 4.56's and detroit posi or gov-lock??

    [/ QUOTE ]
    There is no 14bff that will just bolt with 4.56's and a detroit.
    He got that brand new rearend(i'm guessing) from an army surplus and that would be a 1 ton setup rearend. Only military 14Bff's got detroits, no civilian rigs came with it. You are asking for the exact rearend that you wan't used, you won't find it unless you are lucky or wait long enough to find a 3/4 14BFF with 4.56's and a govlok. They are rare though, especially in a 3/4 ton.

    Oh and you don't want a detroit locker.
     
  10. chev4life

    chev4life 1/2 ton status

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    Re: 14 bolt in my \'87, what is needed?

    I can find many 14 FF but the SF is the tough one, if I can find it cheap enough I will just rebuild it. I see them on ebay for $400 before shipping which I think is way too much. What trucks would I need to find in a junkyard that would have them? I am assuming many 2500 gmc/chevy trucks? Any particular years to look for? What should I spend through a yard to get one for rebuilding? What would a rebuild kit, gears, and gov-loc cost for the SF?
     
  11. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

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    Re: 14 bolt in my \'87, what is needed?

    Look for a 2wd 88'-later 2500 that has a 350 because it will be a light duty and have 6 lug axles still. Many of the 90's 1/2ton trucks with the HD suspension got the 14SF that is 6 lug, the z71's will have a gov-lok. THe problem with the later model 4wd axles is they are wider than the earlier axles because they started making the wheels with much more backspacing. I have heard that the wider rears just about match the wider front width that our front axles have...but I haven't seen it in person to know for sure.

    Most will probably have 3.73's in both 1/2 ton and 3/4ton with a few 3/4tons having 4.10's. Gov-loks were an option under any of these trucks, not just the z71 but you will just have to run the 3 letter code on the axle tube or open the diff to find out. I wouldn't pay more than a couple hundred bucks for a 14BSF that is basically what ready to go and I would be hard pressed to give more than 75 or 100 bucks for one that I would have to tear apart and rebuild.
     
  12. 87BrnRsd

    87BrnRsd 1/2 ton status

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    Re: 14 bolt in my \'87, what is needed?

    Good guessing! I did get mine from a military surplus yard. Oh, and why not a detroit? Sure, they clunk a little, and chirp the tires some, but they arent really as bad as everyone makes them out to be. I can go around a turn as fast as I want, and I have never noticed mine. The only time I do notice mine is having to pull out into fast moving traffic, where it will chirp the tires maybe 3 chirps. Other than that, I dont hardly notice it.
    -Harrison
     
  13. chev4life

    chev4life 1/2 ton status

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    Re: 14 bolt in my \'87, what is needed?

    Cool thanks for the info, I will call around and see what some invintory is about. If I find one with bad brakes can I slap my 1/2 ton ones on there? What should I look for at a yard to make sure I am not buying junk or will most places have them off already?
     
  14. 87BrnRsd

    87BrnRsd 1/2 ton status

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    Re: 14 bolt in my \'87, what is needed?

    No, your 1/2 ton brakes will not work on the 14. Im not sure about the 14sf, but I know that the 14ff has massive 13 inch drums. Oh, and overhall kits shouldnt bee too much. One thing I saw you listed as an overhaul part that is not needed is gears. Gears will run you about $200, but are almost always not needed in an overhaul.
    -Harrison
     
  15. chev4life

    chev4life 1/2 ton status

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    Re: 14 bolt in my \'87, what is needed?

    When I say gears for an overhaul I assuming I will not find a rear with the ratio that I want. Has it been done or is it possible to convert a 14 ff to 6 lug with new axles?...or is that just a bad idea and would cause too many problems.
     
  16. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

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    Re: 14 bolt in my \'87, what is needed?

    I actually thought of converting a 14BFF to 6 lug but a local shop qouted me about 3,000 bucks. Custom axle shafts have to be made and converted to semi float. IT is a big expensive job. I would look for the right 14BSF or go the simplist route and just buy a 14BFF and matching front 8 lug D44/10B and get new rims.
     
  17. chev4life

    chev4life 1/2 ton status

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    Re: 14 bolt in my \'87, what is needed?

    Was just looking at performancewheel.com and they dont even make an 8-6 lug adapter so if i did go with the FF I would have to upgrade the front. Dont have that kinda cash laying around and have no space to grab a parts truck. Looks like gears in the 10 bolt or a 14SF.
     
  18. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

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    Re: 14 bolt in my \'87, what is needed?

    Well as far as cash goes...(prices are what it is in my area)
    regear stock 10bolts... $1,200
    find a good 14SF with 4.10 gear ratio for say $300, regear front to match new rear $600= $900
    find a 3/4ton set with 4.10's and a better rear 14BFF instead of a SF...$400 Maybe $100 bucks in brake parts, chrome covers, what ever you wan't to do before install, new wheels (wheels vary so you decide on that price) $400+$100+ unknown wheel price = $500 + wheels.

    I paid $400 bucks for my 3/4ton setup with 4.10 gears and a rear gov-lok. New pinion bearings in the 14BFF and new chrome covers for both. About $600 total. I ordered wheels and tires at the same time before install.
     
  19. skelly1

    skelly1 1/2 ton status

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    Re: 14 bolt in my \'87, what is needed?

    I have 33's with a 4" lift. The 1990 K5 has 246K miles on the stock 3:73 gears in the corp 10 bolt axles. The rear end has been clunking for the last 15K miles. I wheel it about 5 times a year and have not broken an axle, u-joint, nothing yet. I am personally comfortable with re-gearing my 10 bolt axles and installing eaton posi's front and rear. The complete rebuild kit with posi and precision gears can be had for $600 on ebay, and I've been quoted $250 an axle to install them. For $1700 I'll have new gears with posi's, the goddammed thing done in a day, and probably will never worry about breaking anything for the rest of the k5's california life. I'm an engineer. Leave the engineering to the engineers. I've seen more f' ups when people try fabricating stuff than I can shake a turd at. IMHO.
     
  20. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

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    Re: 14 bolt in my \'87, what is needed?

    [ QUOTE ]
    I have 33's with a 4" lift. The 1990 K5 has 246K miles on the stock 3:73 gears in the corp 10 bolt axles. The rear end has been clunking for the last 15K miles. I wheel it about 5 times a year and have not broken an axle, u-joint, nothing yet. I am personally comfortable with re-gearing my 10 bolt axles and installing eaton posi's front and rear. The complete rebuild kit with posi and precision gears can be had for $600 on ebay, and I've been quoted $250 an axle to install them. For $1700 I'll have new gears with posi's, the goddammed thing done in a day, and probably will never worry about breaking anything for the rest of the k5's california life. I'm an engineer. Leave the engineering to the engineers.

    [/ QUOTE ]
    First off your ONLY running 33's and my guess is that they are an A/T or a simple M/T that isn't over 12.50 wide.There is a big difference between a 33" A/T than a 33" bogger. I would personally bet money that a 33" bogger would long before break something than even a 35" A/T would. I'm not one bit suprised that you haven't broken anything yet because you probably aren't running a truly "offroad aggressive" tire, have a 350 with tons of miles on it that wasn't overly strong brand new anyway, and I am very curious what "wheeling" you were doing.

    You are looking at 1,700 bucks with your ebay deal and installation, go for it! I personally wouldn't spend near that much on 10 bolts but thats me. They have and probably will continue to hold up just fine for you because you probably haven't used your K5 in a manner that GM didn't consider in their design. As for the rest of us that have rubber that is more agressive and/or larger than a 33" A/T or M/T, do some heavy towing, and are running way more power than a stock 350 with 246,000 miles... 10bolts aren't near enough.

    As for engineering, yes I left the engineering up to the engineers and used the best axle they could engineer, the GM corporate 14 bolt full floater and swapped it under my truck because it is identical to the stock 10b as in spring perch width and pinion angle. How stupid of me and many others for swapping out the notoriously weak 10b for a heavier duty 14BFF that bolts in like it belongs there, has the benifet of bigger brakes and better towing capabilities and a rearend that will outlast a 10B. /forums/images/graemlins/rolleyes.gif
    [ QUOTE ]
    I've seen more f' ups when people try fabricating stuff than I can shake a turd at. IMHO.

    [/ QUOTE ]

    I agree, some people shouldn't be allowed near a torch and welder but... Have you ever seen a monster truck in action? A professional rock crawler? Awesome examples of custom fab work by talented people.
     

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