What differential and what gearing?

Ask technical questions about your Ford Bronco II here. Technical write-ups on your axle swaps, engine swaps, chop tops, etc. are encouraged.
Post Reply
stevenf
Posts: 96
Joined: Sat Mar 08, 2008 11:32 am

What differential and what gearing?

Post by stevenf »

I have a GM 12 bolt that Im working on and Im pretty sure it has a posi unit it in. I was thinking of selling the posi and getting a mini spool but I want it to be a on/offroad rig. Will the spool cause REALLY fast tire wear from turing? Should I keep the posi and go with a spool for the front?
Also, It has 3.07 gears right now. Before I reasembled it I was going to buy a D44 front and match whatever gear ratio the D44 had(because I know it will be higher then 3.07. Then I started thinking about long term. Should I go ahead and go with 4.10 gears if I plan to run 33's, or would 3.73ish gears run it fine?
vabronconut
Posts: 268
Joined: Thu Mar 20, 2008 4:04 am
Location: CENTREVILLE, VA

Re: What differential and what gearing?

Post by vabronconut »

stevenf wrote:I have a GM 12 bolt that Im working on and Im pretty sure it has a posi unit it in. I was thinking of selling the posi and getting a mini spool but I want it to be a on/offroad rig. Will the spool cause REALLY fast tire wear from turing? Should I keep the posi and go with a spool for the front?
Also, It has 3.07 gears right now. Before I reasembled it I was going to buy a D44 front and match whatever gear ratio the D44 had(because I know it will be higher then 3.07. Then I started thinking about long term. Should I go ahead and go with 4.10 gears if I plan to run 33's, or would 3.73ish gears run it fine?

if you have 3.08's now with a posi and on a budget i would go 3.73's that way you don't have to change carriers. but you can find great deals on 4.10's with carrier on ebay all day long. only thing is you have to reset pinion depth. 3.08's are definetly not for wheeling and will kill you with 33's. spools are definetly not for street use. usually a dana 44 will come with 3.55's which will work OK with 33's just have to wheel allot in low range.

what transmission you running?
87 bronco II 93 5.0 HO, NP435, 44 sas
stevenf
Posts: 96
Joined: Sat Mar 08, 2008 11:32 am

Re: What differential and what gearing?

Post by stevenf »

Right now its a the stock automatic in my 89BII. I plan to run that for a while and then do a VW turbo deisel with a toyota 22r standard trans.
vabronconut
Posts: 268
Joined: Thu Mar 20, 2008 4:04 am
Location: CENTREVILLE, VA

Re: What differential and what gearing?

Post by vabronconut »

stevenf wrote:Right now its a the stock automatic in my 89BII. I plan to run that for a while and then do a VW turbo deisel with a toyota 22r standard trans.

that sounds sweet. with that i would gear down though at least 4.10's like you said would be great
87 bronco II 93 5.0 HO, NP435, 44 sas
stevenf
Posts: 96
Joined: Sat Mar 08, 2008 11:32 am

Re: What differential and what gearing?

Post by stevenf »

After lots of research, I dont believe this is a posi unit. Should I go with a spool or would the stock diff. with a spool up front be benefitial enough?
vabronconut
Posts: 268
Joined: Thu Mar 20, 2008 4:04 am
Location: CENTREVILLE, VA

Re: What differential and what gearing?

Post by vabronconut »

stevenf wrote:After lots of research, I dont believe this is a posi unit. Should I go with a spool or would the stock diff. with a spool up front be benefitial enough?

Spool up front would be a huge help. just keep the lockouts unlocked on all pavement
87 bronco II 93 5.0 HO, NP435, 44 sas
Post Reply