johnny.race

Diffs

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I ran the alignment bar through a couple of OEM length/uncut housings today in order to check their suitability for a job. Sometimes when a certain pinion offset and width of diff is wanted, it can be got by cutting only one side of correctly selected factory width housing.  The challenge then becomes one of sourcing that width that is in a usable condition ...especially on the side that you are not going to shorten. 

Candidate on the bench.

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The first side looks pretty good. Its almost on and for a factory ute diff with a zillion mils on it - I'd call it straight. Note, the bearing cup assembly can't be pushed on by hand when its being held center to the axle axis by the alignment bar. But take the bar away and it'll slip straight in and work/look correctly. Pity this is the side that's getting chopped.

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Meanwhile at the other end ...

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Near all of the OEM width ones I've checked (but I don't do all of them) are somewhere inbetween these two. Its a funny old world ... demanding tolerances measured in 0.000"s is the only acceptable standard for some parts of them while other parts ... try but yeah ... nah. lol!  

Ps. My bar and dummy bearings are good if you were wondering and the stuff I do comes out straaight as! (really)

Churr.

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Major diff sharn for this weekend... So I bought a new diff, and it came attached to this:

Screenshot_20190811-144017__01.jpg.d5625ba2fa39cb2a6a3023eb84dcf934.jpg

 

Explorer was in Aucks with a dead trans for the same price as wrecker wanted for a complete disc to disc diff outa the same, so thought I'd drive up from Hams and transport back. Ring the dude up and get him to climb under the truck and check the tag, 3L73 yuss it's a 31 spline LSD 3.73 8.8, perfect. Mad mission up there showing up after dark, bundle it on the transporter without really any inspection getting home late last night. Then while basking in the 90s luxury Ford cockpit this morning I notice this on the centre console:

Screenshot_20190811-175158__01.jpg.dd244197f9695de82fdf6d5395d77063.jpg

 

Initially super excited holy shit has a moonbeams air locker in it, but then dawned on me I drove all the way to Aucks to pick this thing up and now I still have no LSD, as open/full locker setup less than ideal for what's sposed to be a fast road ute. So now can't decide if it's a win or loss, prolly come out ahead if I sell it to fund another diff (or new internal bits for this one) but mo time and wheeling and dealing while I should be trying to get this damn ute finished... 

As an aside also found this wedged under the truck, looks like someone's been explorer red necking 

Screenshot_20190811-180135__01.thumb.jpg.904f55630f365d16c10b296b7d65f84a.jpg

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Will be interesting to see what the center section is like, you might be able to return it to lsd easily 

From memory all the parts for the diff are quite cheap on rockauto, apart from spider gears. I ended up finding a lower km one at pick a part and got another set of spider gears which were good. They seem to be prone to damage

I got stuff for mine off rockauto and found mustang cobra has better lsd bits so got those instead of exploder ones  

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Yeah, was thinking could just flick the arb carrier and compressor, switches etc and use that to fund one of the carbon clutch Ford performance LSD units ex the US, they pretty cheap so potentially break even for a brand new inside bits diff. Thing is the housing is also drilled for the air fitting so might be better to just sell as a complete diff for someone's offroad project and try and find another standard one for the hilux, hmmm... 

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It's actually ~40-50mm too narrow, so was just gonna adjust with spacers (cheap) or new wheels (not cheap). Mostly after the 8.8 as a cheap way for extra strength and discs to boot. Are you running the same in yer Valiant? 

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Ah yeap, different length axles is another thing that dawned on me today re these diffs. I was under the assumption they were centre pumpkin style but after having a measure up the passenger side is ~100mm longer than the drivers side (as measured from the yoke centre to the leafs). This is not so bad in my application as gas tank is on passenger side and driveshaft in old setup was touching cloth so this would give a bit more clearance there, am wondering what impact this might have on harmonics though? The Hilux hanger (is a 2 piece d shaft setup) is actually also 30mm offset to the drivers side, but still not enough to allow front and rear shafts to run on the same axis... Any comments from you diff gurus whether this is likely to cause problems? 

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Yeah, that'd be right ... near all Hilux diffs run two the same length axles and feature a pinion that is offset towards the driver side around 28mm in OEM form. Matches your hanger off set pretty much well.

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Any diff that is running 2 axles the same length has a pinion off set from center. Most diffs that feature differing length axles in the rear (in OEM form) will have the pinion centered.  

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Yeh gets a bit awkward with the tube lengths with one being offset and one being centered.

Will be going trutrac eventually but am interested in the borg warner center conversion for the time being.

 

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On 04/09/2019 at 19:54, Esky_addict said:

Yeh gets a bit awkward with the tube lengths with one being offset and one being centered.

Will be going trutrac eventually but am interested in the borg warner center conversion for the time being.

 

Yeah, there is a lot of work and figuring out to get everything where they need to be I would be guessing. The distance between each axle differs between the big Ford and the BW78. I have narrowed both and one you do everything from the rear meaning the driver axle is on your right hand side. The 9" is done from its from front and the same axle is now on your left. What a mind fuck, lol. 

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I am posting couple of pics so someone can have a look at them. Axle resplining stuff.P9121861.thumb.JPG.9aaba1d2edf7c5ff872a340af61cc10b.JPGP9121863.thumb.JPG.500751fc0ed0401fb2c2be9096578704.JPGP9121862.JPG.007c6ec70b8dab929874cb26313a14f2.JPG

BW78 Falcon axle shortened and resplined for use in the passenger side of an early 9". Disc brakes are the added bonus.

P9121864.thumb.JPG.743443e50cf722f0cc742c2d79328bf0.JPG 

 

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sorry to butt into this thread but it seems the only way to show a pic of what I hope to have made. This is a HSS version with many more teeth. Reduce the number to 4 or 5  and change them in inserts.

SANY0080.JPG

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On 14/09/2019 at 15:27, furyimp said:

sorry to butt into this thread but it seems the only way to show a pic of what I hope to have made. This is a HSS version with many more teeth. Reduce the number to 4 or 5  and change them in inserts.

SANY0080.JPG

Cheers mate. I was wondering what it was going to look like. What diameter are you going for?

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