CTIS vs non CTIS lower hub gears

Steel Soldiers is supported by:

Frost0071

Member
47
7
8
Location
Indianapolis/Indiana
Does somebody know if there is a size difference between CTIS and non CTIS lower gears in the hub?
I have the new spindles already but I don't know if I can use my old gears.

This is the size of the new CTIS spindle. Does somebody have a normal spindle laying around and could measure it for me?
IMG_7846.jpg

Thanks
 

Coug

Well-known member
746
353
63
Location
Olympia/WA
I checked the manual, the A2 lower gears (CTIS) have a different part number than the lower gears for the earlier (non CTIS) trucks. I don't know if this is only because the CTIS ones have a higher load rating than the older ones, but I also couldn't find anywhere that said they are interchangeable when searching the parts online.
 

Frost0071

Member
47
7
8
Location
Indianapolis/Indiana
I also checked the manual and saw the different numbers but I'm not 100% sure.
This is why I would like to know the diameter of the old spindle.

I'm sourcing the parts at the moment to add CTIS to my 87 M1038 and I would like to have everything here before I rebuild my hubs.
 

Retiredwarhorses

Well-known member
Steel Soldiers Supporter
2,695
250
63
Location
Brentwood, Calif
to install CTIS spindles you need new control arm covers, new rods for the round ends, and a few various parts for assy.
unless your adding CTIS, your going to need a few more things and it’s not worth it.
 

Retiredwarhorses

Well-known member
Steel Soldiers Supporter
2,695
250
63
Location
Brentwood, Calif
I checked the manual, the A2 lower gears (CTIS) have a different part number than the lower gears for the earlier (non CTIS) trucks. I don't know if this is only because the CTIS ones have a higher load rating than the older ones, but I also couldn't find anywhere that said they are interchangeable when searching the parts online.
there is a shim added underneath the bearing cone, one of the spacers is specific to CTIS spindle as the new spindle is not square cut but instead is tapered.
 

Coug

Well-known member
746
353
63
Location
Olympia/WA
Is CTIS really that bad? I already have the parts beside of the internals from the hub's.

I also have a compressor setup installed just not completely wired up.
View attachment 805966
Not so much that it's bad, there's just no way to keep that many moving parts in the system from leaking. Unless you run the truck/compressor every day or two, you'll come out to the tires resting on the run flats, and then having to wait to drive until everything airs up. Trying to find and repair every little leak will pretty well drive you insane. I'm not saying every truck will be that bad, some may take a week or more to air down, but pretty much all of them do.

Then if a line leaks excessively, or gets torn out or fails while driving around, you have to go around and disable it at all the wheels when you notice. If you don't figure it out soon enough, you then have to air up each tire manually.

If you use a computer to control it that is anything like the ones we had in the LMTVs, then it will randomly deflate the tires and you'll have to shut down, unplug everything, then reconnect and start up again and wait for the tires to refill (which takes a while for an LMTV)

If you are constantly going on off road excursions where you need to air down then back up, then yeah, it might make sense to have it. If you only go off roading occasionally, then all the downsides outweigh the benefits.


If it were me, as others have mentioned run some hard lines to a point where you can easily plug in an air hose, then just do manual airing up/down of the tires. Might take a little longer when you are doing it, but a lot less that can go wrong. Adding a larger air tank somewhere in the rig would make it go a little faster.
I know the one time I took my rig off roading I got flagged down and asked if I had a compressor installed because someone lost a tire off a rim, so having somewhere to tie in for shop air isn't a bad idea anyway. Plus air tools for tire changes, air powered hydraulic jacks, inflating kids toys at the lake, all sorts of uses.
 
Last edited:

TOBASH

Father, Surgeon, Cantankerous Grouch
Steel Soldiers Supporter
1,370
205
63
Location
Brooklyn, NY
I have CTIS on a civilian truck. The plan is to connect only for long drives and off-road camping. Overnight it has quick connects to disconnect.

When you're on the move, CTIS is not an issue, but when parked it will most likely leak.

I had initially wanted CTIS for my M1025a1, but RWH set me straight.

The civilian model is a new-to-me 1995 H1 with factory CTIS. I have decided to keep it, upgrade it, and only connect and use it when driving long distances and camping off the grid.

Best,

T
 

Retiredwarhorses

Well-known member
Steel Soldiers Supporter
2,695
250
63
Location
Brentwood, Calif
I have CTIS on a civilian truck. The plan is to connect only for long drives and off-road camping. Overnight it has quick connects to disconnect.

When you're on the move, CTIS is not an issue, but when parked it will most likely leak.

I had initially wanted CTIS for my M1025a1, but RWH set me straight.

The civilian model is a new-to-me 1995 H1 with factory CTIS. I have decided to keep it, upgrade it, and only connect and use it when driving long distances and camping off the grid.

Best,

T
Best is to get rid of the Brass OEM disconnects and go with stainless braided hoses and quick disconnects.
the hub side QD nipple has a one way ball valve so when unplugged you don’t lose air on the opposite side tire.
 
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website like our supporting vendors. Their ads help keep Steel Soldiers going. Please consider disabling your ad blockers for the site. Thanks!

I've Disabled AdBlock
No Thanks