Hi Sonny
I've decided to reply to the list because I thought the information will be
useful to others.
There are 3 types of the two piece HMMWV rims. One eight bolt (lug studs) &
two 12 bolts.
The eight bolt rim (lug studs) was designed for the bias tire and the two
piece magnesium run-flats. The two 12 bolt rims (lug studs) rim was
designed for the radial and the one piece rubber run-flats. The reason the
military switched to the 12 stud is because the extra 4 bolt give added
strength to support the higher PSI rating of the radials (Bias tires have a
max PSI of 35 & 50 for the radials).
Now you can put the bias tires on the 12 bolt rim but it is not recommended
because it's not designed for the higher psi rating. Someone also mentioned
that the bead could possibly pop off the rim if you're doing some serious.
However, I had radials on a 8 stud for 2 years and never had a problems but
I've done only minor off roading.
Now I mentioned that there are two types of 12 bolts, old and new. It's
pretty easy to tell the difference. The newer one has an alignment hole on
both the outside and inside rim. This also prevents the two type of rims
being mixed together because they have different weight ratings. The old 12
bolt is rated for 3,400 lb and the new one is 3,850 lb. These ratings are
stamped on the rims.
When you put the two half together you need to make sure they are aligned
properly. The new 12 bolt makes is easy. You just stick a fat screwdriver
thru the holds to line them up. The older 12 bolt need 3 special alignment
washer that go between the two rim. They need to be space equally apart in
a triangle pattern to make them rims line up properly. Now, it is possible
to put the two rims together with out them but if you don't get it right
your tires will wobble when you drive. As for the 8 bolt rims I'm not aware
if they require anything to line them up straight.
Another thing you need to be aware of are the O-rings. Each type of rim
have there own O-rings. You'll need to make sure you have the right one.
They are all pretty much the same but with some minor differences. With a
little effort you can tell between the 3 O-rings. For the 8 bolt it's a bit
thicker than the 12 bolt. The two 12 bolts look almost the same but the new
one has a red stripe on it. As someone mentioned earlier, it is recommended
to replace the rubber O-ring that goes between the two rims whenever you
change the tires. Some people like to add silicon grease to the O-rings for
a better seal and to keep the rubber from drying out but I've seen people do
without it too. I really don't know which is the better between the two.
I also mentioned earlier in my earlier post that there are two types of
run-flats. One is the 2 piece metal magnesium and the other is the 1 piece
rubber. The 2 piece goes on the 8 bolt rim and the 1 piece goes on the 12
bolt. From my understanding the two are not interchangeable. The military
switched to the rubber one because I assume they felt it was less of a fire
hazard. I'm sure you know that once magnesium starts to burn it's
impossible to put out.
Well that's about all the information I have on the HMMWV rims. If you or
anyone need pictures, I'll be glad to send them to you. If you need more
information, KASCAR can help you out. I learned most of what I know from
them. You can still order HMMWV parts from them but it is restricted now.
From my understanding they'll only sell you HMMWV parts that are compatible
with the H-1 but not parts that are specific to the military HMMWV. The
only way they can tell you what they can sell is that you send them a list
of part then they get back to you as to what they can give you.
Darrell