Hotweels
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- May 7, 2001
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- City, State
- Calgary,AB
- Year, Model & Trim Level
- '92 EB
I noticed in a few thread's on the board people where talking about the ford 9" so i thought instead of hijacking there thread's i would just post a little info for all to see.
First off some thought's on EB 9"s
The ford early bronco 9" has had some major and minor changes over it's lifespan in the baby bronco's
1966-1971
small axle bearing and 28 spline axles, this is a relatively easy diff to find but not a real upgrade from the ford explorer 8.8" other than the 9"s 3rd member pinion support
1972-1975.5
large axle bearing's where added other than that... eh why mess with something that work's so well?
1975.5-1977
The 9" had 1 final upgrade before the bronco was discontinued, 31 spline axle's made there way into some of the late production bronco's.... i have seen the elusive 31 spline EB axles with my own 2 eye's but have been warned that they are rare and only made there way into the last of the EB's ( pull the shaft's and verify this before purchase!! )
all EB 9"s are 58" WMS-WMS
some people will argue that a 9" has such a low pinion they dont want to lose any clearance by swapping out the 8.8", i have put my 8.8" beside an EB 9" on the floor of my shop and the differance is maybe 1" in pinion heighth if that.
why swap???
when doing a solid axle swap with a ford 1/2 ton Dana 44 you will need to match the new front diff's wheel bolt pattern, depending on your situation it is possible to find a compleat EB 9" for a few hundred dollars....
most people regear and add a locker when doing a lift and if you are doing a SAS you will either need to buy axles that have the correct bolt pattern or buy wheel adapter's plus re-drill your brake drum's or disc's to match the new BP also driveshaft work is required on tall lift's to avoid driveshaft seperation, if you get a EB 9" you will not need to spend money to match your wheel bolt pattern to the 5 on 5.5" ford 1/2 ton pattern and gear's are cheaper for the 9" than the 8.8"
, you will need driveshaft work either way in most cases...
Upgrades
28 spline axles IMHO suck... i have seen stock EB 28 spline axle's they are wimpy, hold a EB 28 spline shaft in one hand and an explorer 31 spline shaft in the other and you will laugh at the EB shaft i am amazed the EB shaft's hold up as well as they do.
The stock 28 spline shaft's neck down between the splines and axle bearing where as the explorer 31 spline shaft's maintain there size all the way thru, the best soloution is simply to buy upgraded shaft's if you plan on running an aggresive locker and 35"s or bigger.
Upgraded shaft's are not cheap but the price may suprise a few people, here is an example of a package deal on custom length performance shaft's.
$371.34usd 35 spline Pro-Street axles, axle bearings, retainer plates & ½" stud kit.
$365.11usd Pro-Street axles (28 - 31 spline), axle bearings, retainer plates & ½" stud kit.
My friend uses the 31 spline axle's in a pro-street coronet 500hp 22" wide micky thompsosn's and a 9" with a mini spool and now has a set of the 31 spline axle's in his EB with a 351W detroit locker and 35" bogger's, these shaft's are BEEFY.
Center section or 3rd member
there are 2 factory version's of the ford 9" 3rd member you will find in a wrecking yard, the small carrier bearing and large carrier bearing 2.892" and 3.063", most 9" 3rd's came with the 2.892" bearing but larger late model vehicle's have the 3.063 bearing.... this is important information to have when ordering the install kit for your gear's.
There are aftermarket 3rd member's available that are much stronger than factory ford stuff but it can be a waste of good money to build a 9" that can handle huge rubber and 1000hp if you only plan on putting it behind the factory V6, one thing to look at is that if you plan on getting 35 spline axle's there diameter at the spline's is 1.5" compaird to 31 splines being 1.315" at the spline's you lose carrier bearing size so you may wish to upgrade your 3rd member to a aftermarket case with 3.250" carrier bearing's to help with bearing life.
$269.58 Heavy Duty street Case with caps & adjusters - 3.250 bearing
$224.42 Ford 9" lightweight spool - 35 spline
Axle bearing's
You have 2 choice's in axle bearing size on a ford 9" big or small, dont mess around here most hotrod shop's can chop the small bearing end's off and weld big bearing ends on while they are doing that it is also the best time to add a back brace on the housing since they can weld on the brace then weld the bearing end's on straight to ensure no warpage to the housing.
Big bearing end's cost around $70-$80usd a pair and a back brace is about $100-$140usd plus a few hour's shop time to install it.
I wont get into disc brake's here there simply are too many option's to list.
If you cant find a EB 9" diff at a reasonable cost or there are none to be found in your area but you still want a 9" another very good option is to snag a full width 9" from a mid 70's to early 80's Bronco or F150 and have it cut down by a reputable shop that has an alignment bar, newer 9"s have big bearing end's chances are they have big bearing carrier's and the only drawback is you will need to have the diff cutdown and purchase new axle's.
While shopping around in wrecking yard's avoid big car's with 9"s most are not realy 9" but are 9.5" they look very very close to a 9" untill you drop the 3rd member out of the housing you will see that the housing is notched to allow the larger diameter ring gear to clear the opening in the housing, these diff's are useless unless you have the resources to build your own crown and pinion beacause the aftermarket has almost no support for this diff.
Best bang for your buck when it comes to putting a 9" in an explorer is to find a big bearing EB 9" with either factory or aftermarket 31 spline shaft's.
cutting down a full width or putting new bearing end's on a small bearing EB diff will cost about the same money, i am not 100% sure on this but i dont think you can use small bearing axle's in a large bearing housing.... look's like i have more reasearch to do
hope this help's somebody.
First off some thought's on EB 9"s
The ford early bronco 9" has had some major and minor changes over it's lifespan in the baby bronco's
1966-1971
small axle bearing and 28 spline axles, this is a relatively easy diff to find but not a real upgrade from the ford explorer 8.8" other than the 9"s 3rd member pinion support
1972-1975.5
large axle bearing's where added other than that... eh why mess with something that work's so well?
1975.5-1977
The 9" had 1 final upgrade before the bronco was discontinued, 31 spline axle's made there way into some of the late production bronco's.... i have seen the elusive 31 spline EB axles with my own 2 eye's but have been warned that they are rare and only made there way into the last of the EB's ( pull the shaft's and verify this before purchase!! )
all EB 9"s are 58" WMS-WMS
some people will argue that a 9" has such a low pinion they dont want to lose any clearance by swapping out the 8.8", i have put my 8.8" beside an EB 9" on the floor of my shop and the differance is maybe 1" in pinion heighth if that.
why swap???
when doing a solid axle swap with a ford 1/2 ton Dana 44 you will need to match the new front diff's wheel bolt pattern, depending on your situation it is possible to find a compleat EB 9" for a few hundred dollars....
most people regear and add a locker when doing a lift and if you are doing a SAS you will either need to buy axles that have the correct bolt pattern or buy wheel adapter's plus re-drill your brake drum's or disc's to match the new BP also driveshaft work is required on tall lift's to avoid driveshaft seperation, if you get a EB 9" you will not need to spend money to match your wheel bolt pattern to the 5 on 5.5" ford 1/2 ton pattern and gear's are cheaper for the 9" than the 8.8"
, you will need driveshaft work either way in most cases... Upgrades
28 spline axles IMHO suck... i have seen stock EB 28 spline axle's they are wimpy, hold a EB 28 spline shaft in one hand and an explorer 31 spline shaft in the other and you will laugh at the EB shaft i am amazed the EB shaft's hold up as well as they do.
The stock 28 spline shaft's neck down between the splines and axle bearing where as the explorer 31 spline shaft's maintain there size all the way thru, the best soloution is simply to buy upgraded shaft's if you plan on running an aggresive locker and 35"s or bigger.
Upgraded shaft's are not cheap but the price may suprise a few people, here is an example of a package deal on custom length performance shaft's.
$371.34usd 35 spline Pro-Street axles, axle bearings, retainer plates & ½" stud kit.
$365.11usd Pro-Street axles (28 - 31 spline), axle bearings, retainer plates & ½" stud kit.
My friend uses the 31 spline axle's in a pro-street coronet 500hp 22" wide micky thompsosn's and a 9" with a mini spool and now has a set of the 31 spline axle's in his EB with a 351W detroit locker and 35" bogger's, these shaft's are BEEFY.
Center section or 3rd member
there are 2 factory version's of the ford 9" 3rd member you will find in a wrecking yard, the small carrier bearing and large carrier bearing 2.892" and 3.063", most 9" 3rd's came with the 2.892" bearing but larger late model vehicle's have the 3.063 bearing.... this is important information to have when ordering the install kit for your gear's.
There are aftermarket 3rd member's available that are much stronger than factory ford stuff but it can be a waste of good money to build a 9" that can handle huge rubber and 1000hp if you only plan on putting it behind the factory V6, one thing to look at is that if you plan on getting 35 spline axle's there diameter at the spline's is 1.5" compaird to 31 splines being 1.315" at the spline's you lose carrier bearing size so you may wish to upgrade your 3rd member to a aftermarket case with 3.250" carrier bearing's to help with bearing life.
$269.58 Heavy Duty street Case with caps & adjusters - 3.250 bearing
$224.42 Ford 9" lightweight spool - 35 spline
Axle bearing's
You have 2 choice's in axle bearing size on a ford 9" big or small, dont mess around here most hotrod shop's can chop the small bearing end's off and weld big bearing ends on while they are doing that it is also the best time to add a back brace on the housing since they can weld on the brace then weld the bearing end's on straight to ensure no warpage to the housing.
Big bearing end's cost around $70-$80usd a pair and a back brace is about $100-$140usd plus a few hour's shop time to install it.
I wont get into disc brake's here there simply are too many option's to list.
If you cant find a EB 9" diff at a reasonable cost or there are none to be found in your area but you still want a 9" another very good option is to snag a full width 9" from a mid 70's to early 80's Bronco or F150 and have it cut down by a reputable shop that has an alignment bar, newer 9"s have big bearing end's chances are they have big bearing carrier's and the only drawback is you will need to have the diff cutdown and purchase new axle's.
While shopping around in wrecking yard's avoid big car's with 9"s most are not realy 9" but are 9.5" they look very very close to a 9" untill you drop the 3rd member out of the housing you will see that the housing is notched to allow the larger diameter ring gear to clear the opening in the housing, these diff's are useless unless you have the resources to build your own crown and pinion beacause the aftermarket has almost no support for this diff.
Best bang for your buck when it comes to putting a 9" in an explorer is to find a big bearing EB 9" with either factory or aftermarket 31 spline shaft's.
cutting down a full width or putting new bearing end's on a small bearing EB diff will cost about the same money, i am not 100% sure on this but i dont think you can use small bearing axle's in a large bearing housing.... look's like i have more reasearch to do
hope this help's somebody.
