The guy finally sent me the tag information. All I can tell is it's an open 3.00 gear. Do the numbers mean anything to you guys?
I think the rearend you are looking at is a 74-86 pickup rearend. They always looked like the heaviest factory rearend to me. They have 3.25 axle tubes that slide into the center section of the housing and are welded in, as opposed to being butt welded. But the fact that the tubes are bigger and the housing beefier means that none of the brackets that you usually have to weld onto the housing are gonna fit without a lot of grinding and fitting. Also, most of the aftermarket housing ends you buy aren't gonna fit exactly the way they were designed (not to say they won't work, but...). I've run into this on a rearend I'm working on now, and after a lot of sitting and staring, I'm gonna take the tubes out of the rearend, find another donor rearend for new tubes (with factory ends) and weld them into the center section. I've narrowed these rearends both ways and am leaning toward tube replacement as the best way out on them, as opposed to replacing the housing ends. Just another free opinion that's worth about what it costs. BTW, I always leave my housing centered, not my pinion.
says 3.00 open differential, the WDM DM code shows up on the fordification id list as something else, but it is most likely an 84 truck, the date code 8F13 is June 13 1984.
I have an 81 F 150 and used to work at a Ford dealership and thought 81 was the last year for the 9" in everything, but vans. My F150 came with a 300 6- c6 279 ratio, 31 spline axles and big bearings.
I thought it was 1986, which agrees with this list... http://www.fordification.com/tech/rearends_ford03.htm .
I am curious as to why you say not to use truck brakes.I put a 67 Bronco rear in my T-bucket,it had 10"drums which were bad,so I located backing plates and drums from a 78 Bronco 11x1 3/4.I redrilled the backing plates to bolt to the early housing.brakes work great and have been driving it for about 3 years.
78 bronco rear brakes are 2.25" wide, aren't they? You can use big brakes, but it's just a strange thing to do on a Falcon. Especially with the large wheel bolt pattern.
Most supercabs had 9" to 86 standard cabs not they are 63" wide. A 89-92 Rangers came with 8.8 57" rear ends
I have an 8" Maverick/Comet V8 rearend that fit perfectly under my Deuce frame. It resembles a 9" in looks, so it fit my needs. I am told that 8" rears won't handle 500 hp with slicks. Anyone agree, disagree ?
The trouble with centering the housing comes when your drive shaft is now off center and doesn't line up with the drive shaft tunnel, such as '33'34 Fords with stock floorboards have. Then you get to raise the floorboard. Another free chunk of advice from a fellow HAMBer.
I can see where it might be a problem on a tight fitting tunnel, but I'm pretty sure the offset is around 15/16". The last 3 I cut down were for cars with aluminum fabricated floorboards (2 Anglias and a 55 Chevy}. The Anglias actually had the whole drive train offset an inch to the right for more room for the driver and steering clearance.
I like to use the truck housings with the 3-1/4" axle tubes,because of a few reasons: 1) The wall thickness on those big tubes is really overkill,you will probably never hurt them with hp or drag strip launches,and the crazy thickness allows them to handle the heat of welding on a spring perch or ladder bar bracket without warping or pulling. Sure,you have to re-grind the radius on most aftermarket brackets/perches that are designed for the 3" tubes,but it's really not that big of a deal.Lay it out with a sharpie,15 minutes with a pencil grinder and you're done. 2) They come with pretty tough 31 spline axles that I usually get reap lined by a local machine shop,so cost is good,and they survive a full season of 6200rpm launches with no twisting in my 2700lb/350hp/stick shift car 3)They come with what are essentially the big Galaxie wagon brakes used on Shelby GT-350's,only they are a little wider. I just have the machine shop re-drill the axles and drums for the 4-1/2" bolt circle 4)They generally come with a 3.50 gear,and the quality of the OEM Ford gearsets far exceeds the quality of the latest "made in India" aftermarket budget lines 5) You can re-use the housing ends when getting them narrowed,which saves a few bucks 6) Once you have a few stashed away you're set for quite a few projects.They can usually be picked up cheap. I know the argument for aftermarket stuff being stronger and possibly more cost effective in the long run is a good one,but it depends on your power level. And I really dig scrounging and using junkyard parts,as opposed to getting everything from Summit or Jegs. Scott Also,you'll have to slot the holes in your axle mounting plates or just fabricate new ones,and get some 3-1/4" U -bolts at the local truck supply place.
If you are going to narrow the housing, I cut just inside the weld on each axle tube. Then I remove the pieces of axle tubes left behind in the center part of the housing. Clean up each axle tube before pressing them back into the center part to whichever dimension you need. You will need to fab up some alignment devices to bolt up to the bearing ends (4x4 3/4" plywood would suffice). Take measurements in at least four ordinal positions, make corrections as necessary before welding tubes to the center part. Best to order the correct axles (with new bearings installed) before shortening the housings. Changing the bolt circle from 5 1/2" to 4 1/2" is sketchy at best due to large access hole in the flange. 10" dia. brakes is plenty enough to slow down the Falcon. New drums and shoes are worth it!
Wait,I just read this again. You call redrilling the bolt pattern from 5" to 4-1/2" "sketchy",but you built your alignment jig from plywood? My last set of axles had thousands of miles,and dozens of 6000+ rpm launches at the track with zero wear showing.I'm actually going to re-use them when I put the smaller engine back in the car for my Son to race it. Also,why would you not upgrade the brakes while you're doing all this work?He did say a 500hp FE was in the plans,right? 120mph trap speeds would make me want all the brake I could get when I step on the pedal. Scott
Actually, my alignment device is far more intricate! Requires cutting apart a 3rd member in order to access the carrier bearings. Then all measurements are taken from a mandrel centered on these bearings. If you paid attention to the wording of my comment, you would have noticed, 4X4 3/4" plywood would suffice. This comment is intended for the "one off" home builder. 1/4" steel plate could also be used but somewhat more expensive.
run a 10 sec 1964 falcon cut down truck 9 in used truck brakes cut down rear and ordered strange axels run 11 in slicks without cutting body moved spring inboard Butch
Do you use the Crites kit to relocate the springs Butch? I'm using their offset shackles in my car,and they sure freed up a lot of room once you move that inner wheel housing back flush with the frame rail. Scott
Lots of good info here on 9 inch rears: http://www.therangerstation.com/tech_library/9InchAxles.shtml Most F-150 9 inch rears BUT NOT ALL that I have seen are 31 spline. The bolt pattern is 5 on 5 1/2 which is easy enough to change to 5 on 4 1/2.
FYI, there was a light duty F100 '80-'83 that had the 4-1/2" bolt pattern. These were 4600-4700 lb GVWR. I think the rear uses the standard truck 9" housing, but comes with 10 x 2-1/2" drums instead of the 11 x 2-1/4".
I use the ford 8.8 ,they are strong,the early Exploders have drum brakes, you can use another rear end shorter axle and get them down to a useable width. They are plenty strong in my opinion and I usually have one with 31 spline axles and a 4;10 posi for under $500. just my opinion.
It sounds like you have time to shop around and maybe get one that is already narrowed to what you need but is obsolete to the guy trying to sell it. By snooping a bit I came up with these axle shaft measurements for 9 inch rears . whel The 75 Broncos starting out with a 58 inch wheel mount width you could get to 54-3/4 with two short axles. That may not be enough for big rubber though. 66-75 bronco small brg RH 29 5/8 66-75 bronco small brg LH 27 1/4 66-75 bronco large brg LH 26 15/16 66-75 bronco large brg RH 29 5/16 74-75 bronco large brg LH 27 1/4 74-75 bronco large brg RH 29 3/4 76-77 bronco large brg LH 27 1/4 76-77 bronco large brg RH 29 11/16 64-66 Mustang LH 26" 64-66 Mustang RH 30 1/8 66-70 Mustang & Cougar LH 27 1/8 66-70 Mustang & Cougar RH 31 1/4 71-72 Mustang & Cougar LH 27 7/8 71-72 Mustang & Cougar RH 31 7/8
BUYERS BEWARE... Early Bronco 9" rears used a long and a short emergency brake cable, short one is fine... but notice the aftermarket long one has 2 hose clamps and a section of black rubber hose slid over the co-axle tube... the co-axle tube is cut in half underneath the hose... there is a foot or more missing... when you anchor the ends you can pull the cable, it taking the slack from the hose, pulling the tube halves together letting the cable extend by a foot before it engages the shoes... no brake brake cable I know of has that much travel... . Checked on ebay, all the long cables I saw had the black hose and a hose clamp at each end... please check different pix, some show one with a kink that couldn't happen with an uncut tube... . Local ford rearend guy says '78 Malibou [10" brake] works for the long cable... It has 5" of threaded steel shaft at the forward end, great for adjusting... 67" overall cables... 52" uncut co-axle tubes... reversed prong clips to secure them, 1/2" hole- anchor measurement... ... hope it saves someone else multiple trips to the parts stores... .
Was there ever a final determination as to the overall width? The stock axle width is 56". Of the several round body "gasser style" Falcons I know of, each uses radiused wheel arches, and leaves the tires sticking out a few inches. The rear axles that they used are 58"-60", and about 3-1/2" backspacing on the wheels. Any wider that that will be a dance of backspacing, or funny looks.
I had a 1967 chevyII. I went to a local bone yard and took a 1959 ranchero 9" out of it and bolted it into the 67 chevyII. Leaf spring perch and 'U' bolts fit. Than I put centerline wheels and 9' slicks on it. tire were tucked under 1/4 panels 3/4 inch on each side. I hope you have good luck like I did.
Your pu axle uses two 31" axles for 63" wheel face to wheel face you can buy 31 spline Bronco axles that are 27 and 29" In the $200 - $250 range With the prices out there now a 8.8 out of a Ranger would be my choice 90 to 93 being the narrowest If you can find an FX4 truck it should have 31 spline axles.
Used a 70's Econoline 9 inch under my last pro street Morris Minor. Hudlow's 4x4 shop narrowed housing cut and resplined the axles and redrilled the axles and brake drums to 5x4 3/4 to fit my Chevy wheels. Bought a Speedway 4.11 posi 31 spline chunk. Everything fit and worked like it should. Stock carriers with a 4 speed ,you better be careful with sticky tires you can blow the pinion out of the top of the housing. Did that with a small block and p/g with a trans brake. Went to a Summers Housing.
Considering what you are using it for, nothing you have there is going to be of service as is. Even the stock carrier. If you inspect it and it has plenty of meat around the pinion pilot bearing, it might be ok but a lot of them don't and break there, even in stock application. If I were you, I'd look for an early bronco unit which would get you pretty close on width. And get one complete with brakes, you don't want to be piecing that stuff together. Then just see how tough it is and replace/upgrade parts as needed. 500 hp 4 speed car on slicks will break parts.
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