Rear hub upgrade

Jtmoney714

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I’m looking to get rid of my rear micro stub set up and go with a mid board or outboard set up. I’ve been looking at the gear one, Tatum and Jamar kits. The Jamar is an outboard set up while the gear one and Tatum set are mid board. Anyone have any reviews or comments or something that has worked for them?
 
No input on your question concerning the different mid boards. My questions is why are you doing the upgrade? What are you trying to accomplish? Not trying to second guess you, just curious what your gaining?
 
No input on your question concerning the different mid boards. My questions is why are you doing the upgrade? What are you trying to accomplish? Not trying to second guess you, just curious what your gaining?
I’m running micro stubs now with the smaller bearing and 36” paddles. I drive accordingly but wear through bearings a season. So I’d like to stop doing all of that and just have the right stuff on the car.
 
Check with Parker first, but Pro Am also makes an HD microstub specifically built for big tires and HP. I would go this direction before a true outboard or mid board. Outboards are not good in the sand since the outer boot doesn't rotate and consistently fills with sand.

 
Personally, I would just jump up to the 33 spline HD bearing. Saves you from cutting the trailing arm apart and would be a big upgrade from the 27 spline. The HD link I posted above requires a new flange on the trailing arm.
 
Personally, I think midboards suck for maintenance. I have the rbp super 99 microstub kit. He uses dana 60 unit bearings, and turns the wheel flange down. I figure if they an hold up the front end of a 1 ton truck, on 37" tires, pulling a 40' toy hauler, I'm probably ok. Plus it may be a far easier upgrade for you. Just a thought.
On the midboard subject, I have 3 close friends that run the gear one set-up with zero issues.
 
I’m running micro stubs now with the smaller bearing and 36” paddles. I drive accordingly but wear through bearings a season. So I’d like to stop doing all of that and just have the right stuff on the car.
I’ll be following on this situation for sure!
I’m in the same boat as you, and going through the Jamar bearings as well. I asked some industry gurus about the pro-am ones and was still recommended the midboard upgrade as the best route, but it’s a lot of money with all the work and parts. Also others have said I should open and put my own grease in the Jamars, but I don’t think this is possible?
Cheap me says I’ll probably just try those expensive pro-am ones next as I’m told this will be an 8k and up upgrade with fab, parts, and labor to go midboard? But sensible me says, “buy once and cry once” and just do the upgrade…
 
I agree with the Gear One customer service and quality. I had a old set of Mid boards and they helped me get them back in action. Only compliant is it cost as much as a new micro stub kit would have been to rebuild them.

Curious how many people have wiped out the larger 33 spline micro stub bearing? A Timken or similar quality bearing. Kartek now offers a even larger micro stub bearing kit. It has a 4 bolt flange.
 
I agree with the Gear One customer service and quality. I had a old set of Mid boards and they helped me get them back in action. Only compliant is it cost as much as a new micro stub kit would have been to rebuild them.

Curious how many people have wiped out the larger 33 spline micro stub bearing? A Timken or similar quality bearing. Kartek now offers an even larger micro stub bearing kit. It has a 4 bolt flange.
I’ve got the 33 spline 3.60 diameter ones and got 1 to 1.5 seasons, and followed the directions perfectly for install etc. when I was at the sand show I talked to a few people that know way more than me about it and they were like it’s par for the course, upgrade to midboard.
 
I’ve got the 33 spline 3.60 diameter ones and got 1 to 1.5 seasons, and followed the directions perfectly for install etc. when I was at the sand show I talked to a few people that know way more than me about it and they were like it’s par for the course, upgrade to midboard.
The problem is the 3.60" size bearing. Regardless of spline the 3.60" size bearing is the weak link. Big upgrade from the 3.6 to the 3.9 bearing.
 
But the 3.90" bearing and a huge 36" size paddle and how heavy of a car???
 
I’ve got the 33 spline 3.60 diameter ones and got 1 to 1.5 seasons, and followed the directions perfectly for install etc. when I was at the sand show I talked to a few people that know way more than me about it and they were like it’s par for the course, upgrade to midboard.
Ya we’re in this together then. I don’t mind spending the money to have the right stuff. It looks to be an ordeal to get the 3.9 bearings. The rebuildable Kartek ones I haven’t heard good things about and they are like 600$ a pop. I already have 33 spline stubs. But I have twisted one with less horsepower and smaller tires. Cheapest route would be to machine the holes in the trailing arms for the 3.9 bearings. That would be about 1400$. But I don’t know if I completely eliminate my issue.
 
Rbp micro super 99 uses the timken 515006 bearing. They are very affordable. The OD of the wheel flange needs to be turned down to fit in the rotor hat.

But the question remains if the 3.90 timken bearing can handle the big 36" tire. All of my experience has been with a 33 sand blaster size tire on a 2400 pound or lighter v8 cars and the bearings have been lasting 8+ years.

Crazy you twisted the splines on the stub axle. Was the castle nut a 36mm or 46mm size nut?
 
Rbp micro super 99 uses the timken 515006 bearing. They are very affordable. The OD of the wheel flange needs to be turned down to fit in the rotor hat.

But the question remains if the 3.90 timken bearing can handle the big 36" tire. All of my experience has been with a 33 sand blaster size tire on a 2400 pound or lighter v8 cars and the bearings have been lasting 8+ years.

Crazy you twisted the splines on the stub axle. Was the castle nut a 36mm or 46mm size nut?
1 3/4” socket. Ya 300m too. It’s my spare to get rolling because it will only fit in that unit bearing now.
 
Do your homework before you get your mind set on outboards. To go Pro-Am that's likely a $15,000 upgrade after it's all said and done.
I've got Tatum 930 midboards, they work ok and I haven't broken anything yet. 2500lb, stock LS3 with 33s, all 300m cvs., car is 94" total width in rear with
31 1/2" axles, moderate cv angle at full droop.
 
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Check with Parker first, but Pro Am also makes an HD microstub specifically built for big tires and HP. I would go this direction before a true outboard or mid board. Outboards are not good in the sand since the outer boot doesn't rotate and consistently fills with sand.

I've run outboards since 2004.
Never had sand in the outer boot.

Outboards have huge bearings.
 
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