• Welcome to H4O! For a reduced ad experience, please login or register with the forum.

Hummer H3 HD Dana 50/ CV shaft upgrade

atvspeed4

Well-Known Member
Messages
1,173
Location
massachusetts
They are still working on them at the fab shop. We noticed a leak on both axle ends and pinion seal that we are trying to troubleshoot on our long term test mule (dana 50 with trutrac in 2009 H3T) want to figure that out before we ship. We think it might be due to overfilling as the fill plug location on the HP cover is far too high for this application and blew out the seals after a fluid change.
 

atvspeed4

Well-Known Member
Messages
1,173
Location
massachusetts
New seal design has been implemented and housing was machined differently so hopefully that fixes it. I am supposed to pick up the new assembly next week and will get installed to start testing.
 

atvspeed4

Well-Known Member
Messages
1,173
Location
massachusetts
Hit us with some updates on this... I hope development and testing is going well.

Having a slight vibration we are trying to track down on passenger side. Not sure if its the km2s or CV issue. Soon as we sort that out we should be good to list for sale. Unfortunately focused on finishing a 6.0L swap in an alpha we bought before we will have time for more testing.
 

atvspeed4

Well-Known Member
Messages
1,173
Location
massachusetts
Good morning! Any updates on this Atvspeed4?

The pallet of 10 completed housings and shafts is staring at us daily! Unfortunately we have not had a chance to dig into the slight vibration issue. We have been scrambling to find new vendors to help us get inventory back in stock on all of our kits without the "covid" lead times or price gauging. Its been a non stop battle past few months calling, sending out RFQ, visiting shops etc.
 

06 H3

a.k.a. "The Jackal"
Messages
9,350
Location
Meridian, ID
The pallet of 10 completed housings and shafts is staring at us daily! Unfortunately we have not had a chance to dig into the slight vibration issue. We have been scrambling to find new vendors to help us get inventory back in stock on all of our kits without the "covid" lead times or price gauging. Its been a non stop battle past few months calling, sending out RFQ, visiting shops etc.
I might get my ass chewed for this one....first, I applaud you for the work on trying to make a strong diff option on the H3, it is not an easy feat. You claim to have 10 housings done that involve extensive machining, I doubt that is a cheap endeavor and while it is none of my personal business on how you run your company I cant imagine having 10 housings with lots of custom work done is good on cash flow....and to just ignore one small vibration issue from selling diffs to people who have been asking for updates since 2019 is crazy. I would think tracking down a vibration issue is a priority and hoping it isnt a design issue because that could make those 10 housings paperweights. I know other items are out of stock but I bet none of them are as big of a cash flow issue as these. 2 guys who were avoiding a SAS already went that route due long wait times. That is 2 less customers on a big purchase item...and the market is already small.

If the diff ever comes out it will be cool as hell to have this option.
 

atvspeed4

Well-Known Member
Messages
1,173
Location
massachusetts
I might get my ass chewed for this one....first, I applaud you for the work on trying to make a strong diff option on the H3, it is not an easy feat. You claim to have 10 housings done that involve extensive machining, I doubt that is a cheap endeavor and while it is none of my personal business on how you run your company I cant imagine having 10 housings with lots of custom work done is good on cash flow....and to just ignore one small vibration issue from selling diffs to people who have been asking for updates since 2019 is crazy. I would think tracking down a vibration issue is a priority and hoping it isnt a design issue because that could make those 10 housings paperweights. I know other items are out of stock but I bet none of them are as big of a cash flow issue as these. 2 guys who were avoiding a SAS already went that route due long wait times. That is 2 less customers on a big purchase item...and the market is already small.

If the diff ever comes out it will be cool as hell to have this option.

No ass chewing necessary. Not to go into the inner workings of the company but the volume of the smaller kits we sell has a much larger effect on cash flow than the 10 housings and shafts we have sitting in a crate do. Its a cool product we are excited to get moving on but they will be a small percentage of our overall company sales so we need to do what is best to keep everything else moving. The market is not as small as you may think. Sure it is not a jeep market but we are one of the only companies competing in it for a few niche vehicles. It sounds cheesy but we do not release any product until all the bugs are worked out and determining if the vibration is due to a variation in aftermarket CV length or due to the manufacture not following exact specifications is something we take seriously. Being in business ( designing, testing, carrying real product liability insurance) since 2011, we must be doing something right. I promise this will get done but we are spread thin. This is a smaller of several companies we run so at times we are spread thin, especially with the arrival of a new baby ugh lol
 

06 H3

a.k.a. "The Jackal"
Messages
9,350
Location
Meridian, ID
I appreciate your post. I think I may be skeptical at times (and others) as we have seen many come and go making promises and then they disappear, with that said you do have other Hummer products so you are staying around.

It definitely is a cool product and I do appreciate you making sure the product goes through the proper testing. I have bought parts that don’t go through that testing and it’s annoying when issues occur. I just thought the vibration would be a quick thing to discover and that you would push to find out so you can start selling product that’s just sitting around.


Running a business is tough, especially being short handed and having supply delays.

-Chris
 

atvspeed4

Well-Known Member
Messages
1,173
Location
massachusetts
Any updates?

We attended the Vermont Pilgrimage overland event this past weekend put about 10 hrs of road driving and tons of wheeling on it. Its tough we keep swapping parts to try to narrow the vibration down but come up empty handed. We have two test vehicles with them installed and vibration is in both but more pronounced in one. Starting to think it might be the extra rigid mounting, roller bearings for shafts instead of needle bearings, much larger rotating mass of the shafts and large CVs along with the full U-joint driveshaft that has no "give" in it like the stock CV drive shaft does.
 

EndeavoredH3

Well-Known Member
Messages
371
Location
Arizona
We attended the Vermont Pilgrimage overland event this past weekend put about 10 hrs of road driving and tons of wheeling on it. Its tough we keep swapping parts to try to narrow the vibration down but come up empty handed. We have two test vehicles with them installed and vibration is in both but more pronounced in one. Starting to think it might be the extra rigid mounting, roller bearings for shafts instead of needle bearings, much larger rotating mass of the shafts and large CVs along with the full U-joint driveshaft that has no "give" in it like the stock CV drive shaft does.

Is this vibration something thats very pronounced? Or something faint?
 

atvspeed4

Well-Known Member
Messages
1,173
Location
massachusetts
Is this vibration something thats very pronounced? Or something faint?

The one that is more pronounced feels like your tires aren't balanced but driveline related. There is nothing wrong with the setup we have swapped CVs, pulled cover to check diff and bearings, checked wheel bearings. We have put a ton of miles and wheeling on the new design and it has held up great just this last annoying issue.
 

Guerrero

Well-Known Member
Messages
124
Location
Spain
How is this going on atvspeed4? I really want that diff in my truck, did you figured out the vibration cause?

I suppose you tried a stock driveshaft in it, to eliminate ujoint driveshaft from the ecuation, and needle bearings in the side bearings

Could you too test the differential in a testing bench? That will be a easier way to be close to the differential when vibration occur, plus reducing the time to install and unistall from the truck, and a good opportunity to investigate the cause of the vibration...just want to launch ideas that I suppose you already tried but in case something aim you in another idea or whatever

This is amazing, and I really want that diff in my truck, despite of that I will install soon a stock elocker in my stock diff to have a spare locking diff, but this differential that you are creating will be the definitive weapon the stock h3 need to be an actual baddass offroad machine...thank so much you and your team offering this!!

P.D: Will be offered a electronic locker instead of an air locker?
With the new differential in a lower position to reduce cv axle angles, the stock skid plate will be necessary to modify?

Thanks,
Guerrero
 

atvspeed4

Well-Known Member
Messages
1,173
Location
massachusetts
How is this going on atvspeed4? I really want that diff in my truck, did you figured out the vibration cause?

I suppose you tried a stock driveshaft in it, to eliminate ujoint driveshaft from the ecuation, and needle bearings in the side bearings

Could you too test the differential in a testing bench? That will be a easier way to be close to the differential when vibration occur, plus reducing the time to install and unistall from the truck, and a good opportunity to investigate the cause of the vibration...just want to launch ideas that I suppose you already tried but in case something aim you in another idea or whatever

This is amazing, and I really want that diff in my truck, despite of that I will install soon a stock elocker in my stock diff to have a spare locking diff, but this differential that you are creating will be the definitive weapon the stock h3 need to be an actual baddass offroad machine...thank so much you and your team offering this!!

P.D: Will be offered a electronic locker instead of an air locker?
With the new differential in a lower position to reduce cv axle angles, the stock skid plate will be necessary to modify?

Thanks,
Guerrero

On our two test rigs we have narrowed it down two two different potential causes we are working through.

#1 On one of the trucks it seems to be the inner tripod joint hitting the diff flange due to being compressed too far. While the CV shafts are from the same vehicle year make or model there is only one part number from NAPA that is the right length to work and any variation from this part number (even from NAPA for the same vehicle platform) is too long and bottoms out while turning.

#2 Both our trucks are running our much firmer diff bushings but the dana 50 uses much more substantial diff brackets that are very rigid. That combined with the Ujoint only driveshaft seems to be transmitting vibration. When we take driveshaft out the vibration goes away in this truck. Going to get the shaft balanced again to verify thats not the issue.
 

Guerrero

Well-Known Member
Messages
124
Location
Spain
On our two test rigs we have narrowed it down two two different potential causes we are working through.

#1 On one of the trucks it seems to be the inner tripod joint hitting the diff flange due to being compressed too far. While the CV shafts are from the same vehicle year make or model there is only one part number from NAPA that is the right length to work and any variation from this part number (even from NAPA for the same vehicle platform) is too long and bottoms out while turning.

#2 Both our trucks are running our much firmer diff bushings but the dana 50 uses much more substantial diff brackets that are very rigid. That combined with the Ujoint only driveshaft seems to be transmitting vibration. When we take driveshaft out the vibration goes away in this truck. Going to get the shaft balanced again to verify thats not the issue.

So it seems first case is just to choose the correct part number, yes?

About the second case, what about installing a stock driveshaft and test? That way you will be sure if its the differential, or the ujoint only driveshaft. And then focusing in balancing the driveshaft? Just launch ideas

Keep the nice work! Thanks!
 

atvspeed4

Well-Known Member
Messages
1,173
Location
massachusetts
So it seems first case is just to choose the correct part number, yes?

About the second case, what about installing a stock driveshaft and test? That way you will be sure if its the differential, or the ujoint only driveshaft. And then focusing in balancing the driveshaft? Just launch ideas

Keep the nice work! Thanks!

Just need to find a stock driveshaft and time but yes exactly thats the plan to see if the stock driveshaft will fit and also alleviate the vibration. We are wrapping up a motor swap on a 2009 but once that is done we will take time to do another round of troubleshooting the diffs.
 

atvspeed4

Well-Known Member
Messages
1,173
Location
massachusetts
We have been in the process of moving our shop so things havent been progressing quickly. We did narrow down the vibration on one of the test trucks to the driveshaft and transfercase so that was a huge win. Still need to track down vibration on the last truck. The crate full of shafts and complete housings was one of the first things we moved and I forgot how heavy that was.
 
Top