Driveshaft/Hub Stud Issues
It's been nearly a year since
my last update to Project Money Pit. I have done a few upgrades
since then, In January I posted an article on
beefing up the
stock Toyota axle housing after discovering I had bent mine. At the
same time I also installed
studs for the steering arms. So far the new housing has been working
well, no signs of bending. The bigger knuckle studs also solved the
problem of the original studs stretching over time, eventually coming loose and
snapping. I have been checking the steering arm studs before every trip
and they have maintained their torque for the past few months. When I was
swapping out the knuckles I also installed new studs and dowels in the wheel
hubs. I was still finding loose hub bolts from time to time and I figured
some fresh factory studs would alleviate this problem; it didn't, more on this
A gearing upgrade was also
installed in January. I received an 8:1 gearset for the transfer case and
beefed up the
case mounting system to handle the anticipated loads the new gearing would
generate. After a couple months with the 8:1's I can say I am very happy with
their performance. My old 117:1 crawl ratio was adequate for most stuff
but on really technical climbs I still wanted slower wheel speed for finer
control. The 8:1's really delivered, providing a 156:1 crawl ratio which feels
just right with the 37's. For the easy stuff on the trail I find myself
using 2nd gear which is 83:1. I'll post more on these when I get some more
time in with them but so far no complaints.
I did manage to find a new weak
point, the driveshaft flanges on the pinion end of the shafts. After a
while mine tend to get ground up pretty good, eventually shedding enough
material that the u-joint cap retaining clips are no longer held in place. The
u-joint cap then pops out and that pretty much ends the day. Even if I had
a spare u-joint I cannot retain the caps anymore. This same thing happens
to the ears on the driveshaft end and when that happens I have to get that end
of the shaft replaced.
My solution was to weld a 3/8"
washer over the retaining clip, basically providing more material to have to
grind through before the u-joint retaining clips are knocked loose. In theory,
once the new welds are ground down to the point where the washer is knocked
loose I can re-weld another washer in there. We shall see if this pans
out. To attach the washers I laid down a few tack welds at a low power level and
then let the end cool, repeating this until the washer was completely encircled
with weld material. When I was done I flushed out the old grease.
Next up where some hub related
upgrades. Best I could figure the stock hub studs were stretching due to
my usage beyond their original design intent, I mean, could you even buy 37"
tires back in 1980? For stronger studs I turned to
Front Range Off-Road Fabrication and their new upgraded stud kit complete
with 12 8740 chromoly studs and lock nuts (made by ARP). From what I
gathered on the internet the theoretical yield/tensile strength of
160,000/190,000 psi is a nice upgrade over a class 10.9's 150,000/136,000
psi. I honestly think the stock studs are closer to a grade 5 since they are not
very hard to drill so their numbers would be even lower.
Along with the upgraded studs I
had Hendrix Motorsports machine the locking hub and wheel hub to accept 4 more
dowel pins. This product is not yet on their
so you'll have to call if you have any questions. It ran $100 for the set
(that includes adding the 4 dowel holes to 2 locking hubs and 2 wheel
hubs as well as new dowels). The first thing I noticed when sliding the new
locking hub over the 6 dowel pins is it is a nice and tight fit, no slop like a
While I was in there I also
installed some new front wheel bearings. The best price I found was from
4x4 & Off-Road, for $45 dollars a side you got two bearings and all the
required seals. They also have a great price on stock knuckle studs and
Speaking of cone washers, I
hate getting those things out, so much so that I actually purchased a tool
that was supposed to eliminate the hassle of pulling the locking hub. The
tool bolts on where in place of the locking hub dial and allows you to pull the
hub and cone washers by turning a jack screw which bottoms out on the axle
shaft. Try as I might I could not get the cone washers to come off and still had
to resort to the old hammer/screwdriver/cuss method of removal (and yes, I did
remember to remove the retaining clip on the axle). I tried the tool on the
other side with the same results so I am not sure it was worth the $20 since I
still had to pry the cone washer open and work them off one at a time.
Once I got the locking hub off
of the drivers side I discovered one broken dowel pin. It was an odd
break, deep inside the wheel hub so the pin actually still seemed functional.
On the passenger side I found
one broken stud. I am fairly certain this broke when I was checking the
stud torque values at the Hammers, I felt it give when the torque wrench hit 20
ft-lbs. It was most likely cracked before I checked the torque, either way a 4
month lifespan wasn't very impressive. Time will tell if the upgraded
studs and extra dowel pins are the answer.
The last upgrade is something I
should have done a long time ago, beadlocks. I actually haven't had much
of a problem running my Baja Claws at 4 psi until I started to run water in my
tires. The water definitely lubricates the bead surface making it much
easier to push the tire off the bead. I like the extra stability and
increase in traction the water provides so I knew I'd have to do something.
The other big reason I wanted beadlocks is for the extra strength the ring
provides. As you can see above, after a year of hard use my rims had some
pretty serious rock related carnage on them. I am sure a few minutes with a
hammer and these rims would be fine but some of the other advantages of a
beadlock wheels eventually convinced me to make the leap, one of them being the
ability to pull a tire off the rim on the trail or in camp. Since I don't
carry a spare I would like the ability to apply a patch internally in the tire
if plugs fail to seal it up.
I chose the 18 bolt
MRW beadlock rims
(formally MRT) in a 15 x 8", 2" backspacing. They used to be one of the
cheaper ones but with the recent rise in steel prices they were roughly $30 more
a piece than they used to be. What's that saying, you gotta pay to play?
I also went with the rockcrusher ring option. For an additional $25 per
rim they provide a thicker and wider ring that will keep rocks from getting
stuck inside the rim and the ring also provides protection for the valve stem.