CK5 Network
Repairing, restoring or modifying your ride just got a whole lot easier!

14 bolt FF swap

stock93

Registered Member
Joined
Feb 18, 2004
Posts
68
Reaction score
0
Location
Huntsville, AL
I have an 83 K10 4x4 with 36x12.50 in buckshot radials. It is a stepside SWB. I'm running a 250 inline 6/465/208. I've found a 14 bolt FF out of a 3/4 ton with 4.56 gears. Currently I have open 10 bolts front and rear. I dont wheel really hard and so far I havent had any parts breakage problems. I'm really easy on the skinny pedal. I'm trying to decide if I should swap to the 14 bolt or not. I dont have problem buying new wheels. I dont wheel really hard with it. Its mainly used to go up some jeep trails to camp out and just general playing around off road. I would like to do some moderate trails but nothing really difficult. Do I really need a 14 bolt FF?

If I do decide to go with the 14 bolt being that its out of a 3/4 ton the springplates should be in the correct place right? Would I have to get a different U joint for the driveshaft to connect to the 14 bolt? Is there anything else I have to change with this setup? I know the front will still be 6 lug for the moment and the gears probably arent the same. I of course wont be running it in 4wd with the gear ratios different. Is 4.56 a good ratio to go with for 36-38s with 250L6/465/208?

BTW I did a search.

Thanks,
John
 

stallion85

1/2 ton status
Joined
Jul 11, 2003
Posts
3,657
Reaction score
0
Location
Cedar City, UT
Yes you need the 14 ff. i was doubtful myself but if you are going to run big tires and wheel you will want that reassurance of strength. I am currently in the prcess of making the swap myself. I do mild wheelin but want more!!!! So of course I will need the best I can get. For now it is a 14ff in the rear and an 8 lug 44 up front. You will need the spring plates, maybe new u bolts to accomodate your lift and a conversion u joint. I have been told Napa sells them. Those gears couldn't hurt much neither /forums/images/graemlins/grin.gif
 

4xcrazy

3/4 ton status
Joined
Oct 31, 2003
Posts
9,485
Reaction score
13
Location
Elma, Washington
I did this conversion on my '89 Burb, things i needed were the new u-bolts because the axle tubes are larger, and the new conversion u-joint which i might add is alittle more expensive than the standard deal. Thats about it, mine bolted right up the springs and shocks with no problems.

BTW mine came out of a '76 3/4 ton p/u truck.
 

84_Chevy_K10

Banned
Joined
May 30, 2001
Posts
17,669
Reaction score
0
Location
IL, USA
I am sure you'd rather do the swap in your garage or driveway than on the trail when your 10 bolt explodes, or on the highway when your tire passes you.

With 36s, you're into where you can easily break that rear axle. At the very least, that big 14 bolt will always get you home (always did for me when I trashed the front when I was 3/4 ton).

The 14 bolt full floater was one of the easiest no-brainer swaps for me. Bolt it in and forget it. The only two upgrades you could possibly want are a locker and disc brakes. After that, you're done. No more messing or worrying about the rear...it's a DONE DEAL.

The front on the other hand opens up a whole new can of worms with tons of upgrades.
 

pauly383

Daddy383
Joined
Jul 22, 2001
Posts
16,216
Reaction score
4
Location
Mesa , Arizona USA
Did your truck come with this six cylinder? If it did I'd be willing to bet it came with decent gears already, maybe 4.10's if your lucky. Change the rear to match the front gearing, or the front if you do get a 4,56 rear. Your trans has a good first gear , and your transfercase has a decent low range already. Just some thoughts. /forums/images/graemlins/thumb.gif

BTW , geared right , that six will be ok in a lighter stepside. Will last a long time, and easy on gas. /forums/images/graemlins/waytogo.gif
 

y5mgisi

1 ton status
Joined
Aug 11, 2002
Posts
17,144
Reaction score
272
Location
Portland Oregon
I would say that eventually you are way more than likely to break your rear 10 bolt. That would suck as it would leave you totaly stranded unless you had a spare. That way you could waste your day away by changing out that shaft. I would say getthe 14 bolt and everything you need to change it out (you will need a new you joint napa #348 iblelive). also new u-boltsare a good idea but not neccesary. YOu will need the new 14blt UPPER spring plates that the u-bolts go threw. Once you get all that then get the new gears for the front end(4.56) then you'le be setup. You need them gears for the 36's and 250 . any more questions let me know /forums/images/graemlins/peace.gif
 

stock93

Registered Member
Joined
Feb 18, 2004
Posts
68
Reaction score
0
Location
Huntsville, AL
Thanks for the info guys. Yes this truck did come with the 250 L6 from the factory. It was made in canada and has a block heater if that makes any difference. I have no idea if the PO regeared it but it drives just fine and will pull 70mph with the 250. I usually get around 17-19 mpg if I keep my foot out of it mostly.

I planned on getting a locker in the near future anyway due to getting stuck from having open diffs a couple of weeks ago. I'll just wait until I swap to the 14b ff. Detroits pretty good for the money for these? This is not my DD so I dont mind if it has some bad manners on the street from the locker.

A dana 60 would have to have the spring perches moved correct? I would like to go ahead and get 8 lugs on all 4 wheels so I dont have to carry two spares. Not to mention all 4 of my ball joints need to be replaced, my bearings need to be replaced, I'm going to need rotors and pads pretty soon, and I want to lock the front end.

Thanks again for the help,
John
 

4xcrazy

3/4 ton status
Joined
Oct 31, 2003
Posts
9,485
Reaction score
13
Location
Elma, Washington
[ QUOTE ]
also new u-bolts are a good idea but not neccesary.

[/ QUOTE ]

Yes they are necessary, the 14bff axle tubes are a larger diameter than the 10 bolt tubes, the 10 bolt u-bolts will not fit around the 14bff axle tubes. I had already gone through this little deal when i swapped mine out, had to wait an aditional 4 days for the new u-bolts to arrive. Got them free from Rough Country. /forums/images/graemlins/thumb.gif
 

stallion85

1/2 ton status
Joined
Jul 11, 2003
Posts
3,657
Reaction score
0
Location
Cedar City, UT
I meant if you didn't want to keep the donors u bolts, you guys probably just cut them off at the yard right? /forums/images/graemlins/grin.gif
 

4xcrazy

3/4 ton status
Joined
Oct 31, 2003
Posts
9,485
Reaction score
13
Location
Elma, Washington
oh i get what you were saying,,,my bad,,, no i have never cut them off at the yard, but then again i have never taken them from the yard as they also charge for those things. /forums/images/graemlins/doah.gif
 
Top Bottom