After putting in a nice new button clutch I have now broken the diff. so I was thinking it would be time to put a 9in in with disk brakes. Can anyone suggest a good place to buy from and also is there anything I need to do to swap to disks and have them work fine. Thanks Aaron
need a diff
- Thread starter xt falcon
- Start date
Discs don't allow really great donut inducing park brakes, and take a little to get sorted on the linkage. If you are running dual exhasts, space from the later BW 78 linkage needs to be clear of the left hand muffler.
Never, never buy 9" XB to XC disc brake axles unless they have been reconditioned. A quote from Bob Pinnelli, V8 Cortina and Capri conversion expert
"Repairing 9" disc axles with shrink rings equals Polands Gross National Debt... I've never stripped one that didn't need new axles." This was in 1990.
It could be that a babied 72-70 LTD may yield a good diff, but its wider and it has the American style braking system which is very expensive to get bits for.
My advice is go steal an XH Outback Hydratrack diff, a 28 spline BTR 78 with balls and the lightweight XE disc calipers.
If you want to go 9", build one up from a stronger Aussie market drum to drum housing limited slipper (LSD). All Aussie diffs were LSD, and made like the best F150 diffs. Open wheeler imports shatter, and need a full rebuild before going any futher. One that doesn't have 38 mm bearings. Then get the XE-XH disc brake conversion.
The hemispheres which hold the crown wheel and four pinion gears tend to brake under heavy use.
My Pontiac mate has been working on his full spool diff for his drag car. He says any short cuts with a 9" will yield tears and debt collections. The bits he has got from ebay and so called reputable sources were crud. You can get disc brake ute diffs for less than a good rebuilt 9".
The last option will make you puke. Get the internal drum brake Holden BTR diff. Its narrow enough, and all Commie Drs had discs from 1988 on. My next door neighbour uses the premium option brakes from one on his 454 HQ, and finds the handbrake works well.
Never, never buy 9" XB to XC disc brake axles unless they have been reconditioned. A quote from Bob Pinnelli, V8 Cortina and Capri conversion expert
"Repairing 9" disc axles with shrink rings equals Polands Gross National Debt... I've never stripped one that didn't need new axles." This was in 1990.
It could be that a babied 72-70 LTD may yield a good diff, but its wider and it has the American style braking system which is very expensive to get bits for.
My advice is go steal an XH Outback Hydratrack diff, a 28 spline BTR 78 with balls and the lightweight XE disc calipers.
If you want to go 9", build one up from a stronger Aussie market drum to drum housing limited slipper (LSD). All Aussie diffs were LSD, and made like the best F150 diffs. Open wheeler imports shatter, and need a full rebuild before going any futher. One that doesn't have 38 mm bearings. Then get the XE-XH disc brake conversion.
The hemispheres which hold the crown wheel and four pinion gears tend to brake under heavy use.
My Pontiac mate has been working on his full spool diff for his drag car. He says any short cuts with a 9" will yield tears and debt collections. The bits he has got from ebay and so called reputable sources were crud. You can get disc brake ute diffs for less than a good rebuilt 9".
The last option will make you puke. Get the internal drum brake Holden BTR diff. Its narrow enough, and all Commie Drs had discs from 1988 on. My next door neighbour uses the premium option brakes from one on his 454 HQ, and finds the handbrake works well.
A
Anonymous
Guest
what about adapting a borg warner out of an xe- xd make sure its the one with vented disc, ive seen a few in picka park,
axels are gtho spec standard and shouldnt cost much and is lighter than a 9inch
axels are gtho spec standard and shouldnt cost much and is lighter than a 9inch
Wagon or ute 2.77/2.92/3.23:1 diffs can take a bit of hard yakka. They are up to a wild 302. But they are no 9" er, and some are not even 7 and 7/8 inch diffs! I've seen a few 7.625" 3.08:1 diffs used in the Falcons and Holdens before 1996 which were not up to it! If its gonna be leant on hard, then you need a four pinion post 96 ute diff.
The axle has a 1527 mm track, not 1485mm, so it will need different backspacing on the wheels. You can swap over to XD-XG control arms at the front, and get a track increase. The hydratrack is a very competent BTR diff, which was basically EL GT spec. With its 28 spline axles and disc brakes, it may be found in either 3.27 or 3.45:1 form in the 96 on Outbacks, XG XR6, XH XR8 or as an option on some of the Longreaches. The real trick is paying up and getting the whole thing. Its bomb proof!
Please, if you going to really burn hides, get a 9" fully sorted to what was recommended above. I've seen XD-XF 3.23:1 diffs used behind 300+ hp VG30ETNissan V6's in a mates Escort, but it eventually broke! The best diff is one you'll never have to touch. A good XE diff is still normally only 25 spline, and most are two pinion open wheelers with cone clutches which go on holiday after a few hard torch-ups. It's never had any more than 250 lb-ft hammering it. The 351 XE's got four pinion Limited Slip diffs, and about 305 lb-ft to contend with.
Most Salibury BW 78's are not hot 351 material...except the post 96 stuff. By then, Ford and Holden got its act together.
The axle has a 1527 mm track, not 1485mm, so it will need different backspacing on the wheels. You can swap over to XD-XG control arms at the front, and get a track increase. The hydratrack is a very competent BTR diff, which was basically EL GT spec. With its 28 spline axles and disc brakes, it may be found in either 3.27 or 3.45:1 form in the 96 on Outbacks, XG XR6, XH XR8 or as an option on some of the Longreaches. The real trick is paying up and getting the whole thing. Its bomb proof!
Please, if you going to really burn hides, get a 9" fully sorted to what was recommended above. I've seen XD-XF 3.23:1 diffs used behind 300+ hp VG30ETNissan V6's in a mates Escort, but it eventually broke! The best diff is one you'll never have to touch. A good XE diff is still normally only 25 spline, and most are two pinion open wheelers with cone clutches which go on holiday after a few hard torch-ups. It's never had any more than 250 lb-ft hammering it. The 351 XE's got four pinion Limited Slip diffs, and about 305 lb-ft to contend with.
Most Salibury BW 78's are not hot 351 material...except the post 96 stuff. By then, Ford and Holden got its act together.
A
Anonymous
Guest
we got a 9'' lsd 4.11:1 drum to drum for sale at work it's hanging out of a f150,any idea what it's worth?
Hey XT,
A fully rebuilt 9" installed runs about $3500 in Sydney. A BW78-based conversion less than half of that.
The gyroscopic effect of the 9" rotating mass is generally held to give smoother launches, but for street use, it's just a "J Arthur Rank". You can get a nice BW (as in professional, with preloads and mesh adjusted)buildup and spend the rest somewhere else. Or post it to me.
Mr Knowles - whatever you can get for it. Maybe confirm the centre type, mileage, stud pattern to start with.
Cheers, Adam.
A fully rebuilt 9" installed runs about $3500 in Sydney. A BW78-based conversion less than half of that.
The gyroscopic effect of the 9" rotating mass is generally held to give smoother launches, but for street use, it's just a "J Arthur Rank". You can get a nice BW (as in professional, with preloads and mesh adjusted)buildup and spend the rest somewhere else. Or post it to me.
Mr Knowles - whatever you can get for it. Maybe confirm the centre type, mileage, stud pattern to start with.
Cheers, Adam.
Biggest issue with the F150 is its width! Some years are easy, others are way to wide. Cutting one down isn't hard, but doing it properly is!
There were some 31 spline axles, but some were 9.25" diffs which had the same case but the third member was no where near as strong.
Be carefull what you buy!
There were some 31 spline axles, but some were 9.25" diffs which had the same case but the third member was no where near as strong.
Be carefull what you buy!
Similar threads
All Small Six
1962 Falcon - Swapping a 170 for a 200 plus C4
