Pirate 4x4 banner

2nd Gen 14 Bolt Info Thread (88 to late 90s)

14K views 25 replies 14 participants last post by  charlieboyd65  
#1 · (Edited)
I just picked up a 1995 14 bolt out of a 1995 Suburban. It was very clean, cheap and the perfect WMS I needed. Unfortunately, all my questions regarding the 2nd gen 14 bolts have led me on scattered searches all over the web. Most of the results have been specific questions and/or limited feedback.

I'd love to put together a thread specifically geared towards some info and FAQs for the 2nd gen 14 bolts. If a thread for the 2nd gen axles already exists with a vast wealth of knowledge please post up a link.

Please don't post up info regarding 1st gen axles (or 3rd gen axles - AAM) unless it is a specific comparison, such as: 1st gen common SRW WMS is 67" and 2nd gen common SRW WMS is 65.5".

Below are a couple of things I have found and questions I have. Please add your info, answers or questions as you see fit, and please correct me if any of my information is wrong.

Common differences between 1st and 2nd gen 14 bolts.

  • 1st gen SRW WMS is 67" - 2nd gen SRW WMS is 65.5"
  • 1st gen has drums behind hub - 2nd gen usually has drums that slide on outside of hub (I have heard some 2nd gen axles have it the old way though)
  • 2nd gen has more finned ridges on diff housing
  • Both axles use same gears and bearings (except inner pinion bearing)
    2nd gen axles have a larger inner pinion bearings and a different crush sleeve

FAQs:

  • Does anyone make a bolt on disc brake caliper bracket or do I have to use weld on brackets?
  • What wheel studs can I use that match my kingpin Chevy Dana 60?
  • Should I really worry about having the back of the hubs machined for rotors? I've heard that others run it as is with no problem.
  • Can I use the same rotors and calipers as the 1st gen 14 bolt disc conversions?
  • Can I run the same gears, lockers, etc as the 1st gen axles?
  • Does the 2nd gen use the same axle shafts as the first gen? Are they a direct swap?

If anyone wants to share their parts list for a 2nd gen disc swap, I'm sure there are plenty of us that would appreciate that as well. Any and all useful information or good questions for the 2nd gen 14 bolts are welcome and appreciated.

Thanks,
Charlie
 
#2 ·
"Does anyone make a bolt on disc brake caliper or do I have to use weld on brackets?"

Caliper bracket? I used a ruffstuff bracket for single wheel on my second gen 14b and it worked great

"What wheel studs can I use that match my kingpin Chevy Dana 60?"

Mine were the same thread size and pitch as my older front d60

"Should I really worry about having the back of the hubs machined for rotors? I've heard that others run it as is with no problem."

Haven't hear this but doesn't mean some have to.

"Can I use the same rotors and calipers as the 1st gen 14 bolt disc conversions?"

This is what I did.

"Can I run the same gears, lockers, etc as the 1st gen axles?"

I broke a first gen housing and swapped everything into the new 2nd gen housing. Minus axle shafts.

"Does the 2nd gen use the same axle shafts as the first gen? Are they a direct swap?"

Mine were not. I'm running a van axle and my shafts were different lengths from one to the other. If I remember right the longer one was shorter and the shorter one was longer. Make sense? :homer:

Hope that helps.
 
#7 ·
No clue what year donor. Friend had it sitting in his floor.

Yes bolt on 1st gen disk brake brackets. The ones on his site listed for single rear wheel.

Can't remember on the drums as that's been a long time since I did the conversion.
 
#9 · (Edited)
2nd Gen 14 Bolt Disc Brake Conversion - Parts List

So, after quite a bit of Internet research, I have finally pieced together a parts list that seems to work well for a 2nd Gen 14 bolt disc swap. I picked up most of my parts at Autozone and used their part numbers, but I also included the application so you can get the parts where ever you wish. My total below does not include taxes or shipping.

My 14 bolt is SRW from a 1995 Chevy 3/4 ton Suburban. I have heard that many of the 2nd gen 14 bolts do not have the back of the hub machined flat because the drums were slip over style on the outside. I verified that the back of my hubs were in fact machined, and I'm assuming that was to give a nice flat surface for the head of the wheel studs. Just FYI...

I'll add pics and more info as I find a little time. So far everything fits perfect, just need to burn in the brackets.
 

Attachments

#25 ·
So, after quite a bit of Internet research, I have finally pieced together a parts list that seems to work well for a 2nd Gen 14 bolt disc swap. I picked up most of my parts at Autozone and used their part numbers, but I also included the application so you can get the parts where ever you wish. My total below does not include taxes or shipping.

My 14 bolt is SRW from a 1995 Chevy 3/4 ton Suburban. I have heard that many of the 2nd gen 14 bolts do not have the back of the hub machined flat because the drums were slip over style on the outside. I verified that the back of my hubs were in fact machined, and I'm assuming that was to give a nice flat surface for the head of the wheel studs. Just FYI...

I'll add pics and more info as I find a little time. So far everything fits perfect, just need to burn in the brackets.
did you slide the rotors on? or put them on the back of the hubs? and did your rotors hub center fit nicely or is it sloppy?
 
#10 ·
I seem to remember (this going back 15 years) that the 14bff with the slip-on drums had odd-ball spindles. By that I mean the journals were spaced closer. The hubs had to match the housing. Only 1-ton SRWs (truck or van) and Suburbans got it, 92-00ish range. A 3/4-ton pickup with 14bff (usually BBC or diesel) had the old backmounted drums.
 
#13 ·
AFIK the internals are mostly the same... same gears, etc. Seems the biggest difference is with the slip on drums (can't use standard old school disc swap brackets), and mine is also 65" WMS/WMS instead of 67". The 88+ seem to mostly have slip on drums rather than pressed behind hub. This accounts for the difference in brake clearance and the need for weld on disc brackets vs the standard bolt on brackets.

With that in mind, I've heard of a few that are odd ball with pressed drums, etc.
 
#17 ·
Just a note on 1st vs. 2nd- I had a perfect 2nd gen in a project with factory 4.56 and a detroit. I sold that housing with the project that it fit and kept the carrier and pinion to swap into an earlier housing that I had.

I have since been fighting the worst noise and vibration immaginable once I let out of the throttle and unload the gears. I have been thinking that there is more to a "all 14b parts interchange" than meets the eye. Gear pattern looks good, acceptable backlash, new stradle bearing, and I even took the pinion assembly to DTS and had them set a new crush sleeve thinking I had an issue there.

If my pattern and backlash are good and the pinion and stradle are good, and the gears are quiet when loaded, what would make an absolute f'n racket once I let off at speeds greater than 30mph?
 
#22 ·
the 13x3.5" JB7 drum brakes are highly underrated. Might not be the BEST for a trail rig or crawler due to weight, and its certianly not 'go fast' light.

That said, pick up the porterfield carbon kevlar shoes (SHOE452 is #), run dually wheel cylinders (bolt in) and run your pressure a little higher in the rear.
So much braking surface.. Will stop anything.
 
#23 · (Edited)
I'm running a 14 out of a 93 model 1 ton Chevy sports van. Its 70" WMS and had the older style first gen brake configuration. I used the bolt on Ruff stuff bracket and the usual late 70's k20 parts. The spindle nuts are single nut per side with the small slide-in steel shim and snap ring. Common 9/16 wheel studs. Im pretty sure the tube diameter is larher than the 1st gen by about 1/4". If anyone is curious to know more about this particular model axle, let me know.