I'm looking for any info on puting a 14FF into my '96 Z-71. Is a stock half ton frame strong enough to support this or should some reinforcements be made?? Also when I do put this in I willl use ORD's shakle flip. Will any 14FF from a 3/4ton or 1 ton bolt right in or are the sping perches different widths?? Also are all the axles the same total width?? One more question, is there any better year or years to look for when trying to find a 14 bolt??

Thanks for any info and feedback

Eric

I've been thinking a little about this same exact swap also. I'm not concerned about the frame strength. I'm pretty sure that the spring perches are the same on 3/4 ton and 1/2 ton trucks from those years, so that part should be a bolt-in. Probably need a new driveshaft. I think (there I go again; damnit, somtimes that gets me in trouble) that 14-bolts from SRW pickup trucks in those model years ('89-'98) have the same width WMS-WMS. I'm pretty sure that this is NOT the same number as the 10-bolts we have, but close enough to not make any real difference. Ordinarily, I'd try to find one about the same year as the truck it'd be going into (mine's also a '96); however I know where there's a '99-ish axle in a junkyard that I hope to check for spring perch widths, shock mounts, etc; it has discs. If something isn't right, I'm thinking that I may try to modify it rather than try to swap the disc hardware onto an older one. I've not spent a lot of time researching this yet, it's just been rattling around in the back of my mind for a while. Since the rear swap will mean that the bolt patterns won't match my wheels OR the front, I'd probably just want to go SFA at the same time, and now we've opened up a much bigger and more expensive can o' worms. Those trucks are great daily-drivers, and good for milder offroading, but I'm not convinced yet that I'll use it as a trail rig enough to justify that much bother and expense - especially since I've got something else underway for that purpose. Probably mine will remain as-is unless something breaks badly or the dogs discover oil.

If you guys figure this out, how are you gonna deal with the ABS?

Doesn't the 10 bolt have the ABS style ring gear? My 96 K1500 rear is getting a little sloppy, and I did notice in HOT ROD that someone is making 12 bolt ring and pinions that are ABS compatable. This make me wonder if a old 12bolt could be converted? I really don't have any need for a 14 SF, but the 10 bolt is so foul.......

Not sure what to do when the rear:nuke:

LLoyd - I too am going to do a SFA at the same time as the 14 bolt rear, otherwise the fromt will be the weak link and I'm already sick of replacing hubs and half-shafts. It's staring to get expensive.

Lame - I believe my 96 GMC only has front ABS and no ABS in the rear. I don't see any electronics or sensors going to rear. I know the front ABS is all in the hubs. But I;ve been wrong before!

I've not got as far as the ABS issue yet. I was hoping that a suitable 14-bolt from a similar-year truck would have the same setup and everything would plug in just like stock. Yeah, I know I'm dreaming. I'll try to look at it this weekend, but it can't be a very high prioity.

I'm going out to pick up a 4.3 from a buddy on Sat. He has a '95 light 2500 with the 14 SF..he is also a big chev guy and mechanic, I'll ask him about it and maybe compare our trucks.

I am pretty sure there is a sensor in the top of the diff..sorta like a ARB hose, eyeballing the ring gear.

I found no ABS sensors on my '96 rear at all; and I looked very carefully. No wires going to the axle assembly. Now the ABS may work off the speedometer signal, but I found nothing on the rear axle to hinder any kind of swap.

As far as my sources say you should have some sort of ABS sensor. Anyway, the SF14 should be bolt in, a nice easy swap.

What gears do you have? 3.42's would be a PITA, I have 3.73's so I might look around at the junkyards for a 14 now.....

Mine has 3.73's also. I checked every inch of the axle housing and found NO WIRES. Maybe they're cleverly hidden inside the vent tube or something, but I didn't see 'em coming out the top of that either. Now this wouldn't be the first time that I was convinced something wasn't there that later turned out to be, or vice-versa. ;) Just couldn't find anything. I've not broken anything in the 10-bolt yet, but the gov-loc isn't 'loc'ing so good any more, and the RR axleshaft seal drools 90wt into the drum. Already replaced the seal, didn't help (groove in shaft). Next time I'll get the offset seal, but what a pain.... For the cost of either a new clutch pack for the gov-loc or a Detroit I could probably get a nice complete 14b from about the right year.

Another question (for me) is whether or not we're going to keep that truck. Our second child was born on 2/2/02, and the back seat is hard to get'em in and out of the child seats (2-door extended cab). Also those child seats take up a ridiculous amount of room, and the front seats need to be most/all of the way forward for them to fit. If we do keep it, it'll probably get the full-floater and -more importantly- SFA. I can't keep the IFS aligned - last time I took it in there was THREE INCHES :eek: of excess toe-in and it'd chewed the outer lugs completely off a new set of tires in 3K miles. :( This after destroying a pitman arm, idler arm, and each TRE showing ~1/16 - 1/8" slop. And I've only got 111K miles on it. So really, the IFS has been a lot more trouble and expense than I think I'd ever get out of the 10-bolt.

Sorry for the whine-fest. I'd like to keep it, but I'd also like to have two real axles and four doors.

I have a bent rear shaft, and the locker is moody, lol. I haven't had any problems with my truck, well I did blow a hole in the 4L60E:D but that is normal...right???

The rear seat does suck, but I don't have to sit back there:D

Want to give me your box?

Box is the wrong color, and shipping would cost a bunch. Besides, I need it regardless. :D I've not scattered the 4L60E yet, but it does slip the 2-3 shift. How did you bend an axle shaft?

I bent it on a Astro van that was doing 40mph perpindicular to my path...fawked up the drivers side box side, and cab corner:eek: At least I dented the old boxside when I fell through some ice:D

Yep, that'd do it. I got hit once like that in a '77 F250 SuperCab. I was on a Navy base, had a cop in front of me and one behind me (two in each car). 25 mph zone everywhere, and a 4-way stop. There was a Lt. Cmdr. in a half-ton Dodge that slid 63 feet before he hit me; mashed the grille back to the firewall on that truck, and wiped out the driver's door, back of cab, and box on my Ford - knocked it sideways out of the intersection, and that thing weighed 6300 lbs empty. No damage to the rear axle (60) - it wasn't hit - but it bent the frames on both trucks. They estimated his speed at 87 mph; in a SCHOOL ZONE.

In your position I think that I'd rather swap the housing too; likely that more than the shaft got bent. There are a lot of the smaller 14b SF axles that should bolt in easy and even let you use the same wheels. But if I keep this thing I'll probably go the same route as Masher and the full-floater and SAS, and do it all at once. But I'll need to find a LH-drop 60 first.

I am tempted to SAS it, but I gotta get my Willy's trail worthy first, then I can screw up the DD:D I'm just gonna run the 10 bolt until it :nuke: then look in to a good rear end.

Lame,

Speaking of blowing up 4L60E's... How did you kill it (ie, did it just stop shifting, or start slipping all the time). Did you replace it with a 4L80E?

I use my 99 K1500 Suburban as a tow rig for my FJ60, and am pulling around 6000lbs, so I'm assuming I'm gonna kill the stock tranny one of these days.

I am looking for options...maybe a new TR/DD is in order? :D

Full-size GM trucks don't use ABS sensors on the rear axle at all. Ford does, Dodge might, but GM doesn't - they use the speed sensor in the tranny (2wd) or transfer case (4wd) to monitor the rear axle speed.

For a '96 Z71, get a 14FF from an 88-98 3/4-ton or SRW 1-ton - only difference is the brakes (larger on 1-ton). 2wd or 4wd makes no difference. Spring spacing is the same for 1/2-ton through 1-ton so long as it's a pickup and not a cab/chassis model. You'll only find the 14FF in 3/4-tons with a big-block or diesel.

i did this on my 95 using a 79 van rear end. matched about perfect with my 97 ford dana 60. like he said the 88-98 truck 14 bolt FF and the 92-98 burb FF should line up ( spring pads, shock mounts). not sure on the overall width of that axle though. i thought the spacing was different on the 1 ton and 3/4 ton 14 bolts for those years but not sure.