The 10.5" 14-bolt failed, long story...
04-24-2005, 10:39 PM
#1
The 10.5" 14-bolt failed, long story... For those who do not know I have (had) a 10.5" 14-bolt rear end with an Eaton Posi and 4.56:1 gears in my truck. This rear end was custom converted from full-float to a flanged semi-float type by DRIVE TRAIN DIRECT in Corona, CA.
Basically, the way they built this is that there are female threaded housing ends welded on to the axle tubes after the full-float spindles are cut off. On the axle shafts first goes the spanner nut that threads into the housing, then the seal, then a captive bearing, then a collar that's pressed on to retain it all.
Well, supposedly that collar takes 10,000 pounds to press on. Whatever. The one on the driver's side MOVED. Luckily it did not slide completely off the machined surface of the axle shaft or I might not be here today. I smelled it, stopped, saw the fluid, and drove the remaining 1-mile home. It might have been provoked by the corner I drifted earlier in the day, but hell - it should have held up.
So, I removed both axle shafts and cleaned them up. The driver's side one was ruined from metal-to-metal interference as I expected from the smell. I popped the cover, drained the fluid and inspected the gears and magnet. No debris got that far - gears looked great, thankfully.
Here's a close-up. I didn't take a picture of the rollers, but I'm fairly sure they are not supposed to be SQUARE:
The housing end shows signs of extreme heat, but internally neither the threads or the sealing surface are damaged:
I took the parts down to Drive Train Direct the following Monday to get repaired/replaced. I even found the guy that sold it to me - PAT. I knew I wasn't in for an easy time with them before even pulling in the driveway, especially considering it took them SIXTY-TWO DAYS to built this thing in the first place, and that's not including the 3 days it took them to just return my call to place the order. But, they built it, they know it. Well, I had no idea what I was really in for...
I start explaining to Pat the problem (parts still outside in the car) and that it needs to be looked at to determine if it's salvageable or the axle needs to be also replaced completely. Pat: "We don't build those any more." That's fine I just need mine looked at and repaired. "We don't work on those any more." Okay, can I at least order the parts? "The parts are no long made and are not available." Okay, well the guy in Vegas still sells them, and his looks exactly like mine. "Then call him or get new parts custom machined." I see, so will you at least take a look at it? "There's nothing we can do." Fine, bye.
Drive Train Direct is not interested in supporting, or keeping their customers. I walked in there with $1000 in my pocket and had my checkbook out in the car. I was not looking for a handout or "warranty" work, I've had this thing a while, put lots of very abusive miles on it, and had no problem paying to get it fixed up right. Apparently they no longer have skilled labor and simply assembly Dana rear ends now. Cookie-Cutter Customization. Jackasses.
What my experience has taught me with these people is that I would recommend you do business with them only if I hated you enough to wish you were dead. How's that sum it up?
I spent the next week trying to decide what to do.
I considered installing a full-float 14-bolt rear and even found a set of rims with the help of the guys on the PA forum that matched are available in 5 and 8-lug bolt patterns. I was not real happy about losing my Tahoe Y2K Limited wheels. I love the way those look on my truck - they DEFINE it, and giving them up was not my first choice. That pretty much made the full-floater a last resort. I wanted to stick with the 10.5" housing. It's very strong, I already have the gears and posi for it ($1K by themselves) and losing that investment was beyond what I could accept.
FINALLY, as I was on the BRINK of buying a junked full-floater I found "The Gear Shop" owned by Gary Downs. Gary has taken over and merged his business into the former "Tom's Differentials" at their location on Paramount Blvd. in Paramount, CA. Gary is extremely knowledgeable, knew EXACTLY what I was talking about and has even seen them fail in exactly the same way mine did. He said to bring it on down! In fact, he has a much better way of doing these conversions that has a bolt-on retaining plate with the hole in the wheel flange for removing the bolts just like a Ford 9".
He was there on a Saturday waiting for me to bring the axles and rear end in to him. I saw the new ends going on and they're superior to what I had. They are made for JB6 (11" duo-servo) brakes, not the crappy 10" JB5 ones my truck came with. Their backing plates have different bolt patterns so I am also upgrading the rear drums to the 11" JB6 ones. The new axle shafts are, of course, six-lug. This was no surprise. These conversions are intended for guys with K1500 trucks with huge tires. Those are all 6-lug. Changing it to 5-lug meant knocking the studs out, filling, redrilling, , and installing new studs just as I had done before to the previous conversion. In the time since I had the original rear end built I discovered that Ronal, the company that made the rims for GM's Tahoe Limited, also made them in a 6-lug pattern. Only problem was that the 6-lug version is available only in 17x8.5", not 16x7" like the stockers.
http://www.ronalusa.com/wheels/r36.html
Also, the 17" version does not have the GM-spec specific machined face and is not available as such. That wasn't a problem since I had a full set of 16x7" Ronal painted-face wheels still in their boxes in the garage I bought years ago for drag tires. If I could find tires close in overall diameter with the correct aspects for the 1.5" difference in width I could make the 17's work...
Found them:
Yokohama AVS S/T 245/70 R16 (29.6" diameter) for the fronts on Ronal 16x7" R36 "Haulers"
Yokohama AVS S/T 285/60 R17 (30.4" diameter) for the rears on Ronal 17x8.5" R36 "Haulers"
http://www.yokohamatire.com/TireIntro.asp?TireID=7
They are a little bigger in the back than the front - no problem. I can fudge the gear ratio in the computer to keep ABS happy and I can take out the 1" lift blocks I had in to compensate for the 1/2" of spring the Tahoe had. (All OBS SUV's get this eventually.)
For the following pictures keep in mind there is still no rear end under there and the back is sitting on jackstands making overall height a little over an inch higher than it will ultimately be:
So, that's what's going on with my truck. It will be nice to have fat rubber sized appropriately to the rims without sidewall bulge. It should help with traction. It is unfortunate to part company with the Pirelli Scorpion Zero's I had before but they just don't have the two sizes I needed. Those tires had less than 2500 miles on them too. Oh well... Maybe I'll run Pirelli's in the future again if I can figure out how to get their 345/60 R17 (33.5" diameter) tires onto a set of these rims custom widened to 11" with 4-link and some simple wheelwell tubbing.
For now I'm awaiting completion of the rear end. I should hear something this week...
Basically, the way they built this is that there are female threaded housing ends welded on to the axle tubes after the full-float spindles are cut off. On the axle shafts first goes the spanner nut that threads into the housing, then the seal, then a captive bearing, then a collar that's pressed on to retain it all.
Well, supposedly that collar takes 10,000 pounds to press on. Whatever. The one on the driver's side MOVED. Luckily it did not slide completely off the machined surface of the axle shaft or I might not be here today. I smelled it, stopped, saw the fluid, and drove the remaining 1-mile home. It might have been provoked by the corner I drifted earlier in the day, but hell - it should have held up.
So, I removed both axle shafts and cleaned them up. The driver's side one was ruined from metal-to-metal interference as I expected from the smell. I popped the cover, drained the fluid and inspected the gears and magnet. No debris got that far - gears looked great, thankfully.
Here's a close-up. I didn't take a picture of the rollers, but I'm fairly sure they are not supposed to be SQUARE:
The housing end shows signs of extreme heat, but internally neither the threads or the sealing surface are damaged:
I took the parts down to Drive Train Direct the following Monday to get repaired/replaced. I even found the guy that sold it to me - PAT. I knew I wasn't in for an easy time with them before even pulling in the driveway, especially considering it took them SIXTY-TWO DAYS to built this thing in the first place, and that's not including the 3 days it took them to just return my call to place the order. But, they built it, they know it. Well, I had no idea what I was really in for...
I start explaining to Pat the problem (parts still outside in the car) and that it needs to be looked at to determine if it's salvageable or the axle needs to be also replaced completely. Pat: "We don't build those any more." That's fine I just need mine looked at and repaired. "We don't work on those any more." Okay, can I at least order the parts? "The parts are no long made and are not available." Okay, well the guy in Vegas still sells them, and his looks exactly like mine. "Then call him or get new parts custom machined." I see, so will you at least take a look at it? "There's nothing we can do." Fine, bye.
Drive Train Direct is not interested in supporting, or keeping their customers. I walked in there with $1000 in my pocket and had my checkbook out in the car. I was not looking for a handout or "warranty" work, I've had this thing a while, put lots of very abusive miles on it, and had no problem paying to get it fixed up right. Apparently they no longer have skilled labor and simply assembly Dana rear ends now. Cookie-Cutter Customization. Jackasses.
What my experience has taught me with these people is that I would recommend you do business with them only if I hated you enough to wish you were dead. How's that sum it up?
I spent the next week trying to decide what to do.
I considered installing a full-float 14-bolt rear and even found a set of rims with the help of the guys on the PA forum that matched are available in 5 and 8-lug bolt patterns. I was not real happy about losing my Tahoe Y2K Limited wheels. I love the way those look on my truck - they DEFINE it, and giving them up was not my first choice. That pretty much made the full-floater a last resort. I wanted to stick with the 10.5" housing. It's very strong, I already have the gears and posi for it ($1K by themselves) and losing that investment was beyond what I could accept.
FINALLY, as I was on the BRINK of buying a junked full-floater I found "The Gear Shop" owned by Gary Downs. Gary has taken over and merged his business into the former "Tom's Differentials" at their location on Paramount Blvd. in Paramount, CA. Gary is extremely knowledgeable, knew EXACTLY what I was talking about and has even seen them fail in exactly the same way mine did. He said to bring it on down! In fact, he has a much better way of doing these conversions that has a bolt-on retaining plate with the hole in the wheel flange for removing the bolts just like a Ford 9".
He was there on a Saturday waiting for me to bring the axles and rear end in to him. I saw the new ends going on and they're superior to what I had. They are made for JB6 (11" duo-servo) brakes, not the crappy 10" JB5 ones my truck came with. Their backing plates have different bolt patterns so I am also upgrading the rear drums to the 11" JB6 ones. The new axle shafts are, of course, six-lug. This was no surprise. These conversions are intended for guys with K1500 trucks with huge tires. Those are all 6-lug. Changing it to 5-lug meant knocking the studs out, filling, redrilling, , and installing new studs just as I had done before to the previous conversion. In the time since I had the original rear end built I discovered that Ronal, the company that made the rims for GM's Tahoe Limited, also made them in a 6-lug pattern. Only problem was that the 6-lug version is available only in 17x8.5", not 16x7" like the stockers.
http://www.ronalusa.com/wheels/r36.html
Also, the 17" version does not have the GM-spec specific machined face and is not available as such. That wasn't a problem since I had a full set of 16x7" Ronal painted-face wheels still in their boxes in the garage I bought years ago for drag tires. If I could find tires close in overall diameter with the correct aspects for the 1.5" difference in width I could make the 17's work...
Found them:
Yokohama AVS S/T 245/70 R16 (29.6" diameter) for the fronts on Ronal 16x7" R36 "Haulers"
Yokohama AVS S/T 285/60 R17 (30.4" diameter) for the rears on Ronal 17x8.5" R36 "Haulers"
http://www.yokohamatire.com/TireIntro.asp?TireID=7
They are a little bigger in the back than the front - no problem. I can fudge the gear ratio in the computer to keep ABS happy and I can take out the 1" lift blocks I had in to compensate for the 1/2" of spring the Tahoe had. (All OBS SUV's get this eventually.)
For the following pictures keep in mind there is still no rear end under there and the back is sitting on jackstands making overall height a little over an inch higher than it will ultimately be:
So, that's what's going on with my truck. It will be nice to have fat rubber sized appropriately to the rims without sidewall bulge. It should help with traction. It is unfortunate to part company with the Pirelli Scorpion Zero's I had before but they just don't have the two sizes I needed. Those tires had less than 2500 miles on them too. Oh well... Maybe I'll run Pirelli's in the future again if I can figure out how to get their 345/60 R17 (33.5" diameter) tires onto a set of these rims custom widened to 11" with 4-link and some simple wheelwell tubbing.
For now I'm awaiting completion of the rear end. I should hear something this week...
Last edited by James B.; 04-24-2005 at 10:54 PM.
04-25-2005, 01:09 PM
#2
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Man that really sucks. It sounds like this time it will really be built right. Im very nervous as to how long mine will hold out. Ive been very lucky in the trans dept. I think Im going to opt for the 4L80 as you recommended. That will be going in with the new 6.0 forged shortblock and T trim.
Is there anything I can do to try and extend my current rears life? Other than adding an Eaton when I do the other other things, it is stock.
Is there anything I can do to try and extend my current rears life? Other than adding an Eaton when I do the other other things, it is stock.
04-25-2005, 02:25 PM
#3
The weakest thing is the factory locker. Even the stock open differential has a better chance of survivng high power than the G80 does. You see it many times - the G80 housing breaks apart, the pieces get bound up in the gears which in turn breaks the transmission too. Expensive.
Tahoes and Suburbans make great traction with even stock tires because there is so much weight over the back. In a pickup running small tires can save your rear end because the tires will break traction before the parts can load up enough torque to break them.
The best advice I have for a stock 10-bolt under an SUV with a lot of power is to keep the gear at 3.73:1 or less to reduce the torque to the differential, do not install a torque converter with a stall speed any greater than 2600RPM, install an Eaton Posi, and install a cast aluminum cover. I like the way the Mag-Hytec cover is designed. It does not ned a gasket, instead it has an o-ring in a reverse v-groove in the cover. This allows metal-to-metal contact between the cover and the housing to help re-enforce the housing. Under a lot of torque the housing folds in on it self slightly like pressing the sides of a plastic salad bowl together. The more rigidity you can give that housing the less likely gear teeth contact geometry will be compromised.
Tahoes and Suburbans make great traction with even stock tires because there is so much weight over the back. In a pickup running small tires can save your rear end because the tires will break traction before the parts can load up enough torque to break them.
The best advice I have for a stock 10-bolt under an SUV with a lot of power is to keep the gear at 3.73:1 or less to reduce the torque to the differential, do not install a torque converter with a stall speed any greater than 2600RPM, install an Eaton Posi, and install a cast aluminum cover. I like the way the Mag-Hytec cover is designed. It does not ned a gasket, instead it has an o-ring in a reverse v-groove in the cover. This allows metal-to-metal contact between the cover and the housing to help re-enforce the housing. Under a lot of torque the housing folds in on it self slightly like pressing the sides of a plastic salad bowl together. The more rigidity you can give that housing the less likely gear teeth contact geometry will be compromised.
