|Rear 9.5" Harrop elocker and 410 Nitro Gears on a custom build by Rekon 4x4 in Spicewood, Texas.|
|(68 BIG pics loading)|
|NOV 26 2017|
| This link is about the REAR Harrop equipped diff build.|
Product received for the build. The Nitro Gear package consisted of 410 Nitro gears, master install kits, a new 29 spline front flange,
and solid collars. The 913A612 Truetrac will go in the front 3rd on the left....and the #9378 Harrop elocker will go
in the big 9.5" rear diff.
Here is a link to the front Truetrac with Nitro 410 install....CLICK HERE
| The desired gear ratio was discussed with Rekon 4x4 shop owner Archie Contreras and because the Chevy LS2 crate motor(430 HP) runs|
happier in a lower rpm zone, 410 gears just seemed to make more sense. Going slow offroad will not be a problem.
The 4L65-E is mated to a Landcruiser transfercase.
The tcase has a low gear set from Marks4wd.com.
Installed is also a part-time conversion kit as well so all the stuff up front is not spinning all the time.
|Parts are organized.....solid collar...seals...bearings...shims.|
|Koyo 32010J "conversion bearings" that are sometimes used on 50mm journals.|
|The large inner pinion bearing on the left.....small outer pinion bearing on the right.|
|Nice shim selection with the Nitro kits.|
|For the power involved, the solid collar is the way to go.|
|The Harrop elocker.....|
|Instructions and the wiring harness.|
|No polarity for the 2 wires....both are black so hook them up either way and it works.|
|Nitro 410 gear set......from JustDifferentials.com.|
|Here's the 410 ring that was on the diff that Rekon4x4 sent me.....they are all scuffed up. Unusable.|
|Tooth surface is far too compromised. This kind of scuffing can be caused by extremely low oil.|
|Now to start disassembly....DING! the bearing cap.|
|All 4 bearing cap bolts are whizzed off.|
|That poor pinion.....|
|The original pinion flange looks good on this side....|
| ....and really looks good on the bottom side where the seal lives. That tiny groove is no issue at all....|
especially since I will be using a Marlin "eco" seal that will move the seal contact zone almost .300" higher based on the picture above. .
|The bare 3rd housing has been cleaned up. The new race is now installed.|
|Going down smoothly.|
|An old race will guarantee that the new race is 100% seated.|
|Tapping the small outer race in.|
|I would like to try .050" for the first pinion depth guess.|
|Pressing the new bearing on with the .050" shim.|
| Now to mount the 3rd over the pinion shaft. Only tighten the pinion nut enough to have some pinion bearing preload. |
This is only a paint check so whether it has 5 in/lb or 20 in/lb is not a big deal to the paint.
|To prep the Harrop elocker we need to mount the ring and the bearings.....but first to do a file check and both surfaces have no rough spots.|
|The plastic hammer got it started but this one was a really tight fit.....|
| ....so the press made it look so easy. Easy to damage the stop-tabs and that's the reason my fingers were in constant contact with them making|
sure they never made contact with the press's steel beam.
| You had better have a good eye to make sure the 12 bolt holes are perfectly aligned because the tight fit here meant it would be very hard to|
move it over even a couple thou. I got lucky again and had perfect alignment :)
|Blue Loctite and 81 ft/lb.|
|The new Koyo bearings were also a very tight fit.|
|All ready here.|
|Harrop case is installed and some bearing preload with the proper backlash of about .007"|
|Painted 3 teeth and this drive side looks shallow.|
|Coast is also shallow.|
|Comet tail is tucked into the root too deep so we could go thicker on the pinion shim.|
|Skipped some pics and re-shimmed the pinion to .054"(4 thou deeper). This drive pattern is now "exact" depth but we could go a tinge deeper and will.|
|Coast side....looks exact.|
|The comet tail appears to tell me that the depth is just about right....it's fluffing out to the center a little.|
|So the pinion depth will be tweaked only .002" deeper and now the solid collar can be installed.|
| The 27 spline generic seal on the left(in the kit) and the awesome Marlin seal on the right. |
Gonna use the Marlin for Archie's build.
| On the 4th try, the solid collar was properly shimmed. Marlin seal is then tapped in place.|
Some pictures were skipped but basically then installed the original pinion flange and cranked on the nut til 10 in/lb was measured.
DING the new nut and the pinion end is complete.
|I opened up the grooves for the stop tabs just a little and that did the trick.|
|I now measure 2.5mm of free play.|
|The 4 bearing caps are verified to have 70 ft/lb.|
|Backlash is measured and recorded from every other tooth.|
|Now to pass the rubber grommet thru the hole.|
|RTV helped seal the rubber grommet more effectively.|
|Looks good on the outside.|
|Final drive pattern....looks wonderful.|
|Coast is beautiful.|
|Resistance of the magnetic coil checks in at about 4 ohms.|
|12 volt power is applied to the elocker wires.|
|Turning the ring gear now will cause the 3 steel pins to push into the case.|
|The pins are pushing a locking ring in place.....the locker is engaged.|
|Turning the ring gear in the opposite direction ramps the pin up the other side.|
|The 2 tabs can now be tightened to 10+ ft/lb.|
|The basics are engraved on the ring.|
|A snapshot of the notes.|