Hi....new member here with rear axle tech questions

[K5blazer2nv]

Hi, I am new here....I come from the diesel world being a previous cummins owner. I recently purchased an 88 K5 with 6" lift and 35" swampers, and a 78 K5 with 18" lift and 44" ground hawgs.
Ok...so I blew up my 10 bolt in my 88 Blazer last weekend while out 4x4ing. The guy I bought the Blazer from told me it had 4.56 gears and an Eaton gov lock installed new 6 months ago. Well....I know that the Eaton gov lock is a weak link so I decided to search for a 14 bolt 9.5", which I found one and have started the process of getting it ready for install. So far I have removed the brackets and spring perches, and I purchased a 4.56 ring and pinion...but not a whole lot of time to mess with it after I get off work so it may take a few weeks. This is my only running vehicle at the moment other than my motorcycle, and rain is hit and miss lately. Anyway, I decided to open the 10 bolt lastnite to a$$ess the damage and I find only the ring gear has lost 3 teeth....and it is NOT an Eaton gov lock, but an AUBURN GEAR limited slip! All the spiders look great and it actually appears pretty new from what I can tell. So, my question then is....should I get a new ring and pinion for the 10 bolt and drive it, or is the 10 bolt a complete waste of time no matter what parts are used?

 

[rdn2blazer]

is your 10 bolt in the truck with 35's or 44's?? if its the 35 in tire truck fix your 10 bolt and drive it unless you intend to wheel it hard, then get a 14 FF. if its the 44 tire truck junk it and the 9.5 14 and get a 14 FF 10 1/2 in ring gear axle. why did you decide on a 9.5 14 when a 14 FF is so easy to find?

oh and welcome to CK5.

 

[K5blazer2nv]

I was told that the 9.5" was a straight bolt in with six lug....so I looked for one and picked it up for $100. I quickly learned that it is NOT a straight bolt in, that's how I found this site. I started doing some research about these K5's and what are the best swaps. I still think it will be cheaper in the long run to swap the 14sf since I do not have to change the lug configuration.
By the way, this is for the 35" tired 88'. The 44" tired 78 also has a 10 bolt if you can believe it LOL. I know it wont hold up....but I am not sure what I am doing with that one just yet.....may part out the lift and body. I bought it because the price was right. There is no motor or trans in that one.

 

[dyeager535]

Auburn posi is no good for hard wheeling, and if you already broke a ring gear, why even contemplate sticking with the (known) weak axle?

Do the 14SF and be done with worrying about the next weak link in the 10 bolt.

 

[rdn2blazer]

since your in Sac. look at Gravel Maker for some cool parts for your rig. there a vendor here if you did'nt allready know that. look in the vendor forum.

 

[K5er4Life]

I wouldnt fix the 10 bolt, why put something back in there that you know is going to break easily again. Spend the money on your 14sf and enjoy the strength and never have to worry about breaking a rear axle agan.

 

[rdn2blazer]

I only suggested to fix the 10 bolt IF he was going to drive it mostly as say DD. as I said I would ditch it AND the SF14 bolt and go straight to the 14FF. he could find a bolt in 14FF easy with 4:10's and probably even 4:56's also.

 

[88sub4x4]

Since you have the 14SF already, and it will allow you to keep your current wheels and tires, then you are really doing well. Regear the 14SF. Those axles are around 175% stronger then a 10B, and are lighter then the 14FF. They hold up perfectly under 35's. I wheeled the piss out of mine and it never gave me a problem. The gears are real easy to install in there, and if you want added traction put in a lunchbox locker (if you have an open carrier) or upgrade to an Eaton Posi unit (this is different from a gov-lock). The eaton is great on the street, and gives you the most traction possible without going to a full locker.

Good luck, and welcome to the forum

 

[MaxPF]

I only suggested to fix the 10 bolt IF he was going to drive it mostly as say DD. as I said I would ditch it AND the SF14 bolt and go straight to the 14FF. he could find a bolt in 14FF easy with 4:10's and probably even 4:56's also.

We go round and round with this on this forum. Yes, 14bff's are cheap, but the new wheels (and possibly tires), 8 lug front conversion, etc. to do it right end up costing more money and time. If you're gonna tell a noob to swap to a 14bff, then tell him the whole truth. In this case, the truth is that unless he plans to eventually go with really large tires, then the 14bsf is a simpler and much cheaper swap that will easily hold up to any size tire that is appropriate for a truck with a 10b front (i.e. 37's MAX, with an easy foot or chromos). If big tires and hard wheeling are in the plans (i.e. 38+ inch) then his 10b front end, not the 14bsf, is the limiting factor. This is when a D60 front end comes into play. Since going to 8 lug is a must for a D60 front, then it makes sense to put the stronger 14bff in the rear.