What's new
By:
Filters

MCI 102-C3 coach to RV - Chassis/Suspension

02rexwi said:
I missed the picture of that ID tag. 1.42 is the carrier ratio, 6.58 is the overall ratio.

@ design ride height you're sitting right under 98" hub flange to flange.

The front axle in that set has a limited slip differential, the rear is an air actuated differential lock.

Too bad they're looking for $8500.​
Glad to have you aboard the thread. You and a few others have been quite helpful on this.

6.58 gets me 64 MPH with that particular TM4 motor. Getting close. I put my dial caliper on the screen to get rough measurements at scale and came up with a 23.5" lower control arm length from ball joint center to inner pivot center using a 97.8" WMS-WMS. If that's near accurate, the suspension would have to be at full droop to pull the wheels in enough to be at legal width and the camber would be way off. If push came to shove, I could build new, shorter control arms and grind some off the slip splines. Too much to modify just to make these fit, if you ask me.

The only way to make the pair worth while is if the seller took a much lower offer and I could line up buyers for the tires and t-case right away. Money-wise, the 4000 beams are easy and I already know they fit perfectly.
 
jd8420 said,

I knew it was going to be wide. The wheels that come on them have an extreme amount of backspace. This is a set of those wheels.

https://www.ebay.com/itm/Michelin-16...MAAOSwGY1Zpsb6

If you wanted a higher gear ratio, I know there are at least 2 different common military planetary hub gear ratios for the AT5000. I bet they would work on the ifs version too. The more common straight axle AT5000 has something like 5.90 overall gearing. I think the planetary gears are somewhere around the gearing found in the AT4000 (3.54).
 
02rexwi said,
jd8420 said:
I knew it was going to be wide. The wheels that come on them have an extreme amount of backspace. This is a set of those wheels.

https://www.ebay.com/itm/Michelin-16...MAAOSwGY1Zpsb6

If you wanted a higher gear ratio, I know there are at least 2 different common military planetary hub gear ratios for the AT5000. I bet they would work on the ifs version too. The more common straight axle AT5000 has something like 5.90 overall gearing. I think the planetary gears are somewhere around the gearing found in the AT4000 (3.54).​
There are common military components in the market to speed up the wheel end ratio. You're pretty close on the wheel end ratio
yH5BAEAAAAALAAAAAABAAEAAAIBRAA7
.

There's a whole bunch of ratios available for the 5000 series wheel ends. With that said what you can find in the aftermarket is probably what you're going to be most concerned with. Buying new service parts tends to add up quickly.
 
GLTHFJ60 said,
JNHEscher said:
We're in pursuit of a dream, my good man. 15.x" of wheel travel is definitely impressive on a bus, but suspension flex isn't a big deal to me. The main purpose of the swap is to have all three axles driven and double-wishbone suspension is pretty sweet.



Bingo. I have now seen countless pictures and videos of buses getting stuck in the most ridiculous ways. Numerous bus owners parking in family/friend yards and getting stuck, having to call a wrecker to pull them off the grass. The last two videos I saw were of a Greyhound getting stuck in a Flying J Express driveway because of a big dip that dropped out the drive axle and another of a tri-axle Class A or whatever that couldn't get out of a campground drive because of a big dip. They surely had no problem descending the slope because they could easily control their speed with the brakes on all three axles. But when it came to drive back up with an open diff in a single axle, that's all she wrote. I'm not shooting for hitting mud holes or anything. Just getting ALL the traction on ice, snow, dirt, rocky BLM grounds on plenty of hills and everything in between. I watched some video of a crew taking their RV's into BLM land in Buena Vista. They had to stop so many times to shove rocks under their drive axle tires to get it up there.​
I hear you. I hope you get there, but I feel like this will end up being sold as an uncompleted project for some reason :flipoff2:

Most of that getting stuck shit can be fixed with driver awareness. Plenty of other people in the world who take their buses to interesting places "off-road" and are able to do it without getting stuck. This guy is the first example that comes to mind. The key to his success is walking questionable routes, and being cautious.

https://www.youtube.com/channel/UCtA...LVzUN_OFovA8iA
 
jd8420 said:
I knew it was going to be wide. The wheels that come on them have an extreme amount of backspace. This is a set of those wheels.

https://www.ebay.com/itm/Michelin-16...MAAOSwGY1Zpsb6

If you wanted a higher gear ratio, I know there are at least 2 different common military planetary hub gear ratios for the AT5000. I bet they would work on the ifs version too. The more common straight axle AT5000 has something like 5.90 overall gearing. I think the planetary gears are somewhere around the gearing found in the AT4000 (3.54).​
I remember you telling me about the high backspacing. Even with that, the width of the beam 4000's worked out just right and the 4500 worked as well. I'll dig around to see if theres any way to identify some narrower sets of ISAS 5000's.

As far as gearing, I should be able to work with about anything in the typical ranges because there is a huge list of motor options with varying RPM and torque ranges.
 
02rexwi said,
JNHEscher said:
I remember you telling me about the high backspacing. Even with that, the width of the beam 4000's worked out just right and the 4500 worked as well. I'll dig around to see if theres any way to identify some narrower sets of ISAS 5000's.

As far as gearing, I should be able to work with about anything in the typical ranges because there is a huge list of motor options with varying RPM and torque ranges.​
You'll be hard pressed to find a ISAS 5000 in North America that's narrower.
Europe may have something.
 
jd8420 said,
02rexwi said:
There are common military components in the market to speed up the wheel end ratio. You're pretty close on the wheel end ratio <a href="http://www.pirate4x4.com/forum/images/smilies/wink.gif" border="0" alt="" title="Wink" >
yH5BAEAAAAALAAAAAABAAEAAAIBRAA7
</a>.

There's a whole bunch of ratios available for the 5000 series wheel ends. With that said what you can find in the aftermarket is probably what you're going to be most concerned with. Buying new service parts tends to add up quickly.​
There are some agricultural fertilizer spreaders with the AT5000 that have an overall gear ratio of 17.7:1. Any idea how much of that is in the planetaries vs the ring and pinion.
 
FirstRam said,
GLTHFJ60 said:
I hear you. I hope you get there, but I feel like this will end up being sold as an uncompleted project for some reason :flipoff2:

Most of that getting stuck shit can be fixed with driver awareness. Plenty of other people in the world who take their buses to interesting places "off-road" and are able to do it without getting stuck. This guy is the first example that comes to mind. The key to his success is walking questionable routes, and being cautious.

https://www.youtube.com/channel/UCtA...LVzUN_OFovA8iA​
That skoolie has a single rear axle, makes a difference.
 
02rexwi said,
jd8420 said:
There are some agricultural fertilizer spreaders with the AT5000 that have an overall gear ratio of 17.7:1. Any idea how much of that is in the planetaries vs the ring and pinion.​
If you're talking about the RBR fertilizer spreader it has a very deep reduction wheel end. The overall ratio of the axles that are currently in production is around 8.9:1 That's a heavy duty axle housing. Was designed for 5G loading.
 
arse_sidewards said,
02rexwi said:
I can't get too into the design rational, but in a way, yes 5x rated load.​
And what would be a typical safety factor for a "normal" axle?

Do axles generally have the same or greater safety factor for the knuckles/kingpins/spindles?
 
02rexwi said,

t all comes down to the vocation. Unless it's something special most people use equipment in similar ways regardless of the manufacturer, so the design factors are based on knowledge of what loading vehicles see in operation.

With that said, military is usually one of the most severe and has the highest stakes if something breaks.
 
jd8420 said,
02rexwi said:
If you're talking about the RBR fertilizer spreader it has a very deep reduction wheel end. The overall ratio of the axles that are currently in production is around 8.9:1​
GVW model E350. The axles are around 120" WMS to WMS. They have 650/85R38 tires which are about 82" tall. I can't remember if this is the model number for the front or rear. Axletech model number 872111043A. I think the other one was 872131108A.
 
02rexwi said:
You'll be hard pressed to find a ISAS 5000 in North America that's narrower.
Europe may have something.​
I figured as much. I cataloged everything AT4000 related that I could find a while back. I think I have all common AT4000 model numbers listed with their specs. Very little on AT5000's, but wasn't really bothering because they're rated much higher than what I need. If the 5000 ISAS fit and were priced right, I'd go for them since the 4500's are gone.
[486] said:
dump air from the tag axle bags

and get a locking diff in the drive axle​
Quite doable. Still, I have a preference to install a drive axle at all positions. The tag is fairly redundant, but as I've found in our bus and every MCI that I've see posted with the floor torn up and the comments referring to the stress cracks in the same locations as ours, I've determined that taking the pressure off the tag axle places way too much tension on some of the structures at the front of the drive axle suspension frame. This brings me to desire constant vehicle support at the tag position. There's a bit over four feet between the contact patches of the drive and tag tires. I don't have the distance from the rear bumper to the drive axle centerline on me, but with over 4,000 pounds of engine and transmission hanging behind the drive axle along with the bus shell, I want to eliminate that stress.



Totally appreciating the input. I'm a sucker for technical specs.
Here's the short of what I've got -

AT5000's are rated well over what I need. Especially if I'm placing two drive axles in the rear. Quote from MCI "Rear drive axle is the original one, Rockwell S165WX-4, 3.33 ratio. Load rating is on the VIN tag, 22000 lbs." The tag does not support the weight of the bus, but merely supplements the drive.

The 4000 series works great. Beam or ISAS. My max width in the rear is around 84" (88" if I order wheels with -2" offset) and max for the front is around 90". All three axles to have steering ability.

Does the 5000 series have more planetary gear options available to the public? Do the 4k and 5k not share the same planetary gear plate? Are the 4k and 5k sun gears interchangeable?

I'm still kinda pissed that I missed a great opportunity to crawl around the TAK-4. As we were heading up the on-ramp to I-70 from our usual gas stop in Oakley, KS. on our way to Missouri, I looked over and saw two of the new JLTV's with TAK-4 on a car hauler. I'm betting they're too wide, though.
 
02rexwi said,
JNHEscher said:
Does the 5000 series have more planetary gear options available to the public? Do the 4k and 5k not share the same planetary gear plate? Are the 4k and 5k sun gears interchangeable?

I'm still kinda pissed that I missed a great opportunity to crawl around the TAK-4. As we were heading up the on-ramp to I-70 from our usual gas stop in Oakley, KS. on our way to Missouri, I looked over and saw two of the new JLTV's with TAK-4 on a car hauler. I'm betting they're too wide, though.​
The 4000/5000 nomenclature is typically used to separate loading. There are a few different sizes of wheel end gearing and ratios available within those sizes. There's so many different designs out there that I'd be hard pressed to try listing all the options.

The TAK-4 on the JLTV is a lot different than the TAK-4 on the medium to heavy size military trucks. It's definitely worth checking out if you can pop your head under one. They're pumping those trucks out like crazy, so they'll start becoming more commonplace like HMMVW's in the next few years.
Again, I can't share any technical specs, but if you look at the wheel end components and know the various military axles that are in production on other platforms you should be able to tell what's going on pretty quickly.
 
02rexwi said,
jd8420 said:
GVW model E350. The axles are around 120" WMS to WMS. They have 650/85R38 tires which are about 82" tall. I can't remember if this is the model number for the front or rear. Axletech model number 872111043A. I think the other one was 872131108A.​
Yeah, those part numbers are for GVM. You're fairly close on the overall ratio.
 
jd8420 said,
02rexwi said:
Yeah, those part numbers are for GVM. You're fairly close on the overall ratio.​
GVM is what I meant. Spell check must have changed it. Are the planetaries for the GVM lower geared than the 4.63:1 of the IFS AT5000 or is the difference in the ring and pinion? Trying to get the lowest gearing possible for a big stupid mud truck.
 
Got started on pulling the tag axle tubs out. A good hour or so taking a few dozen bolts out and getting the air spring line off the bulkhead in a tight spot. Amazingly enough, MCI designed the wheel tub bolts to be accessible without removing more than the wheel. If I had been able to lift the bus up by about three feet, I could have rotated the tub so that it would slip right out from the underside. Alas, I do not have a way to levitate our bus, so I gnarled the tub in half with the sawzall. One side down, the other tonight or tomorrow.

I want to put the wheel back on before pulling the other side off for an extra safety measure, but that blocks much of my access again to the area that I want work on. The bolt-on jack stand came to mind. Perhaps it's high time I built the foot for it. I measured 16.5" the OD of an aired up tire to the edge of the wheel center bore.

718.jpg
719.jpg
720.jpg
721.jpg
722.jpg
 
jd8420 said:
Sold for $230.​
I checked the 5000 beams when we got home. About 8" too wide. 4000 beams it is. I was going to check with Jay because we were supposed to be headed back to Oklahoma every two weeks, but that apparently got cancelled. Need two narrow steers and one wide steer. I can work with the gear ratios.

Edit: I take that back. With a wide 4000 up front, I do have 3.8+" to scoot each wheel outward. Kinda want to stick with the same axle type all the way around just for parts redundancy.
 
02rexwi said,

I know you're looking for some 4000's. Did you find anything?
I've got a couple spare 3rd members if you're looking for some cheap spare parts. 1.59:1 ratio.
 
02rexwi said:
I know you're looking for some 4000's. Did you find anything?
I've got a couple spare 3rd members if you're looking for some cheap spare parts. 1.59:1 ratio.​
None yet. I have a few contacts that have some 4000's. It's just a matter of going to get them. Timing, trailer, and tow vehicle are the factors. The other thing is grabbing individual steer units. Most want to sell F/R pairs.

I do want to match diff ratios all the way around. I'll keep your spares in mind.
 
Interesting side note, vetteboy79 apparently mentioned me in his Iceland adventure thread. He posted a very capable bus that he spotted while there and it must've brought my build thread to mind.

The Bovmani. I need it. https://mountaineers.is/about/our-fleet-and-facilities/

Steer tire blowouts are continually spoken of because of the extensive, collateral damage that could come of the incident, as you can imagine. This threat has had me thinking for months that a second axle up front would be the real deal. I never spoke of it because I assumed I would get all kinds of flamed and the crap I would get from patrol would turn it into a laughing stock. That and enforcers of U.S. laws get rather pissy about anything they can't wrap their heads around.

Secondly, the thought of raising the bays a bit for clearance has been a mild thought floating around the back of me brains. As I mentioned in vetteboy79's thread, upon throwing in the towel last night, this thought entered my cranium once more. This time, much more present and broiling at the forefront of my thoughts. I got on the thread today and glanced up to right to see I had 24 notifications instead of the 23 that it had been on for a while. I had a mention that led me to the picture of the Mountaineers of Iceland bus that blew me away. There it was. My ultimate rig. Found their site and have been drooling over the fleet of black beasts all evening. If I'm not mistaken, I believe I see an AxleTech 4000 at the front of one.

753.jpg
 
gavan said,

Start looking for a HEMTT. Seriously. You can get them under 10k and there you go... all your everything you need
 
You must log in or register to reply here.
Top Back Refresh