- Joined
- Oct 21, 2004
- Location
- BFE Desert east of Cali
Ok, so I finally got to installing a TruTrac 912A588 into the stock open diff 1031 in my wagon and figured it's time to update some data out there on the web. First off I'd like to thank Dave Barton for the page he's got, as well as update it a little.
http://www.davebarton.com/volvorearends.html
First off the identification of a 1031 is not quite correct. A 1031 and a 1041 can be a single-rib axle, and a 1030 can be a dual-rib axle (have a 1030 in the 140 with 2 ribs). The axle the TruTrac went into was a 1031 with a single rib and the 1041 that was in the car was also single rib. The 1031 has the larger inner pinion bearing as well.
The 1031:
<o
> </o>
Now for the meat of the project…
Parts required:
New pinion nut spec’d for the Volvo axle (the Dana 30 nut is not the right size)
New crush sleeve (not included in my kit, others may have it)
TruTrac 912A588 (bought along with install kit from <st1:city><st1lace>Summit</st1lace></st1:city> – search the web for a price match and they’ll meet it)
<o> </o>
Dana 30 rear install kit
<o> </o>
Timkin HM89449 bearing and HM89410 race (bought from Autozone)
This is the pinion bearing that’s different from the 1030 and the standard Dana 30. The one on the left is the 1031 bearing, on the right is the 1030/D30 bearing.
<o> </o>
Tone ring from a G80 or skills to make something similar if it’s going into something that requires a speed pickup. The later ones use a 48-tooth ring like shown here, but others may have a 12-tooth ring.
Here’s the G80 tone ring
And the stock open diff tone ring
<o> </o>
Now for the work…
<o> </o>
It’s easiest to remove the axle from the vehicle, but it CAN be done without. Once you’ve got the axle where you’ll be working on it the teardown begins. First the axles come out, then the cover comes off and the old diff comes out. You probably won’t need a case spreader for this part (I didn’t). If you’re doing bearings as well the pinion nut and flange need to come off and then you can tap the pinion gear out with a punch in the center of the gear to avoid damage to the threads.
<o> </o>
You’ll need to split the bearing or press it off and press the new one on making sure to keep the shim in place between the gear and the bearing as this sets your pinion depth. From here the pinion gear can go back in, the new crush sleeve, new outer bearing, the oil slinger (goes right between the bearing and the flange), the flange, and nut. Torque the nut until you get around 2Nm of turning torque.
<o> </o>
Now for the diff. First off the old bearing needs to come off the ring gear side so you can remove the oil slinger, the ring gear bolts, and the ring gear. The oil slinger doesn’t fit well on the TT so I left if off when mine was reinstalled. Using the new bolts from the install kit you can install the ring gear. Torque spec is 26 ft.lbs plus 60* of rotation.
<o> </o>
The tone ring will require a little light welding. I used a G80 tone ring which was easily removed from a spare unit by using a cold chisel to split it, then simply pulling it out. The diameter is just slightly too small for the TT housing, so it will be a little short. I chose to fab up an extra tooth of the same size which worked out quite well, and kept the speedo dead on.
<o> </o>
Once you’ve got the ring welded together you need to set it on the diff at the right location. I used the speed sensor hole to set the installed position, by centering the ring in the hole for the speed sensor.
<o> </o>
Once that’s on a few tack welds to keep the ring in place and you’re set.
<o> </o>
Next you need set up the differential in the housing. You’ll need a dial indicator to do this correctly. I have the setup tools which made this part FAR easier. You will need a way to put the bearings on the diff, remove them, then reinstall them with the correct shims if you don’t have the proper setup tools. Once you’ve got the bearings on you need to set the differential for .005-.006” backlash, plus .05-.08mm of bearing preload. Once you’ve got the shim combination for each side figured out, pull the bearings back off, install the shims, reinstall the bearings, the diff into the housing, and the bearing caps (torque to 22 ft.lbs. plus 60*).
At that point you should end up with something like this…
<o> </o>
Now for the final steps.
You will need to space the speed sensor out about .010” due to the larger diameter of the tone ring. A layer of thin gasket material works for this if you use a diff cover gasket. If you don’t use a diff cover gasket you will need a little thicker spacer. You’ll be able to tell if the sensor will hit easily enough by putting the cover on and using an axle shaft to spin the diff.
<o> </o>
At this point you’re ready to install the cover and the axle shafts, fill with oil, and install in the vehicle. Fill capacity is 1.6L for the 1031/1041 axles. I chose Redline 75w90 for mine and it seems to be working quite well.
<o> </o>
As for the performance, mine’s only been in the car for a day but it’s completely seemless. You really don’t notice it’s there until you really get on it. One wheel in the dirt and the other on the pavement will get you a lot of dust in the air on accel, but the car will get moving quite quickly. One possible downfall which bit me today is if you’re hard on the throttle to a point where both sides break loose you WILL have the tail end trying to pass you up if you’re not paying attention. A hard stab in first had me in this situation when both tires hit a paint mark and let loose. Otherwise normal driving you don’t notice it’s even there, even in parking lots and such.
<o> </o>
Hopefully this helps a few of you out there!<o></o>
EDIT: 11/11/16:
Recent findings pertaining to axles with a steel cover.
Pulled the cover from the 1030 in the 140 which also has a Trutrac, since the cover plug no longer sealed (a shop years ago ran it in too far). Grabbed an aluminum cover from a 1041, bolted it on (FYI, you need longer bolts, get them with the cover, or get that length in 5/16x18 if you're working on a 140). Upon filling it up, it took 1.5qts, where the steel cover combined with the TruTrac would only take 1qt.
Just a cool fun fact.
For those of you needing a tone ring for this installation, here's a discussion about them:
http://forums.turbobricks.com/showthread.php?t=317562
And a supplier:
http://bakaxel.se/catalogsearch/result/?q=Hastighetsmätarkrans+
Specs:
http://www.davebarton.com/volvorearends.html
First off the identification of a 1031 is not quite correct. A 1031 and a 1041 can be a single-rib axle, and a 1030 can be a dual-rib axle (have a 1030 in the 140 with 2 ribs). The axle the TruTrac went into was a 1031 with a single rib and the 1041 that was in the car was also single rib. The 1031 has the larger inner pinion bearing as well.
The 1031:
<o
> </o>Now for the meat of the project…
Parts required:
New pinion nut spec’d for the Volvo axle (the Dana 30 nut is not the right size)
New crush sleeve (not included in my kit, others may have it)
TruTrac 912A588 (bought along with install kit from <st1:city><st1
lace>Summit</st1lace></st1:city> – search the web for a price match and they’ll meet it)
<o
> </o>Dana 30 rear install kit
<o
> </o>Timkin HM89449 bearing and HM89410 race (bought from Autozone)
This is the pinion bearing that’s different from the 1030 and the standard Dana 30. The one on the left is the 1031 bearing, on the right is the 1030/D30 bearing.
<o
> </o>Tone ring from a G80 or skills to make something similar if it’s going into something that requires a speed pickup. The later ones use a 48-tooth ring like shown here, but others may have a 12-tooth ring.
Here’s the G80 tone ring
And the stock open diff tone ring
<o
> </o>Now for the work…
<o
> </o>It’s easiest to remove the axle from the vehicle, but it CAN be done without. Once you’ve got the axle where you’ll be working on it the teardown begins. First the axles come out, then the cover comes off and the old diff comes out. You probably won’t need a case spreader for this part (I didn’t). If you’re doing bearings as well the pinion nut and flange need to come off and then you can tap the pinion gear out with a punch in the center of the gear to avoid damage to the threads.
<o
> </o>You’ll need to split the bearing or press it off and press the new one on making sure to keep the shim in place between the gear and the bearing as this sets your pinion depth. From here the pinion gear can go back in, the new crush sleeve, new outer bearing, the oil slinger (goes right between the bearing and the flange), the flange, and nut. Torque the nut until you get around 2Nm of turning torque.
<o
> </o>Now for the diff. First off the old bearing needs to come off the ring gear side so you can remove the oil slinger, the ring gear bolts, and the ring gear. The oil slinger doesn’t fit well on the TT so I left if off when mine was reinstalled. Using the new bolts from the install kit you can install the ring gear. Torque spec is 26 ft.lbs plus 60* of rotation.
<o
> </o>The tone ring will require a little light welding. I used a G80 tone ring which was easily removed from a spare unit by using a cold chisel to split it, then simply pulling it out. The diameter is just slightly too small for the TT housing, so it will be a little short. I chose to fab up an extra tooth of the same size which worked out quite well, and kept the speedo dead on.
<o
> </o>Once you’ve got the ring welded together you need to set it on the diff at the right location. I used the speed sensor hole to set the installed position, by centering the ring in the hole for the speed sensor.
<o
> </o>Once that’s on a few tack welds to keep the ring in place and you’re set.
<o
> </o>Next you need set up the differential in the housing. You’ll need a dial indicator to do this correctly. I have the setup tools which made this part FAR easier. You will need a way to put the bearings on the diff, remove them, then reinstall them with the correct shims if you don’t have the proper setup tools. Once you’ve got the bearings on you need to set the differential for .005-.006” backlash, plus .05-.08mm of bearing preload. Once you’ve got the shim combination for each side figured out, pull the bearings back off, install the shims, reinstall the bearings, the diff into the housing, and the bearing caps (torque to 22 ft.lbs. plus 60*).
At that point you should end up with something like this…
<o
> </o>Now for the final steps.
You will need to space the speed sensor out about .010” due to the larger diameter of the tone ring. A layer of thin gasket material works for this if you use a diff cover gasket. If you don’t use a diff cover gasket you will need a little thicker spacer. You’ll be able to tell if the sensor will hit easily enough by putting the cover on and using an axle shaft to spin the diff.
<o
> </o>At this point you’re ready to install the cover and the axle shafts, fill with oil, and install in the vehicle. Fill capacity is 1.6L for the 1031/1041 axles. I chose Redline 75w90 for mine and it seems to be working quite well.
<o
> </o>As for the performance, mine’s only been in the car for a day but it’s completely seemless. You really don’t notice it’s there until you really get on it. One wheel in the dirt and the other on the pavement will get you a lot of dust in the air on accel, but the car will get moving quite quickly. One possible downfall which bit me today is if you’re hard on the throttle to a point where both sides break loose you WILL have the tail end trying to pass you up if you’re not paying attention. A hard stab in first had me in this situation when both tires hit a paint mark and let loose. Otherwise normal driving you don’t notice it’s even there, even in parking lots and such.
<o
> </o>Hopefully this helps a few of you out there!<o
></o>EDIT: 11/11/16:
Recent findings pertaining to axles with a steel cover.
Pulled the cover from the 1030 in the 140 which also has a Trutrac, since the cover plug no longer sealed (a shop years ago ran it in too far). Grabbed an aluminum cover from a 1041, bolted it on (FYI, you need longer bolts, get them with the cover, or get that length in 5/16x18 if you're working on a 140). Upon filling it up, it took 1.5qts, where the steel cover combined with the TruTrac would only take 1qt.
Just a cool fun fact.
For those of you needing a tone ring for this installation, here's a discussion about them:
http://forums.turbobricks.com/showthread.php?t=317562
And a supplier:
http://bakaxel.se/catalogsearch/result/?q=Hastighetsmätarkrans+
Specs:
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