Author Topic: Chaining up tag axle  (Read 8306 times)

Offline roadrunnertex

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Re: Chaining up tag axle
« Reply #15 on: November 03, 2006, 10:40:04 AM »
Gosh Folk's
Us older bus owners that own the GMC Buffalos with the optional drop down tag axle are way ahead of the later model MCI and other type buses that are on the road today.
GMC was way ahead of it's time when it came to bus building.

Offline Abajaba

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Re: Chaining up tag axle
« Reply #16 on: November 03, 2006, 05:54:29 PM »
When I was driving for the charter company it was a rule that you not run down the road with the air off of the tag axle.  This would have caused damage to the airbags on the tag axle.

I personally released the air from the tag suspension on several occasions when I got into a situation where the empty bus didn't have enough bite after unloading to drive away from the unloading area.  Once I was someplace where I could get good traction elsewhere in the parking lot, I would put the air back on the tags.  Then when I loaded the passengers I didn't have a problem at the same place as the drop off.

One time I had a passenger get back on while I was moving to the parking area and we couldn't move.  He wanted to know if he should gather everyone else from the passenger load and push.  I let the air off the tags and told him "sit down we are leaving."  He wanted to know what I had done as we didn't slip at all.

I have heard other drivers that have driven with a tag chained up say that the bus wallows like a wounded hippo. 

Yes the tag axle eats tires in tight turns.  A large number of buses making the same tight turn on concrete can really lay down a lot of rubber in a short amount of time.  Our company would use a tire on the steer axle, then the drive axle and finally on the tag axle.  There the tire would end its useful life and then be returned to the leasing company.  I know it is difficult to prevent tight turns that scuff the tag but do whatever you can to prevent these turns and the tag will last longer.

Those tags are there for a reason and I would not want to drive a bus that started out with tags and had them chained up or removed.

Offline Len Silva

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Re: Chaining up tag axle
« Reply #17 on: November 04, 2006, 06:55:18 AM »
Hi Tom C and Folks:

Good post Tom, but you make reference to a 102A2.

Capt. Ron's bus has 5 inch wide front & tag  brakes and 8 inch wide rear brakes.

A 102A2 has 6 inch wide front & tag brakes and 10 inch wide rear brakes., so the engineers obviously adding a lot more braking power for the 2 axle version, while eliminating the tag axle.

I post strictly for informational purposes, so that readers of this post do not compare apples and banannas and:

I Hope this HELPS!!!!


I believe the 96A2 and the 102A2 also had a different wheelbase than the 3 axle coaches.  They didn't just remove the tag.  I also believe the GVW was about the same, not sure about the turning radius.

I'm not sure if the same thing applies to the Eagle Suburbans. I think they just removed the tags and reduced the GVW.  Some converters of entertainer coaches also removed the tags (Caldwell Brothers for one)

Personally, I think if you keep the conversion weight down, a two axle forty footer is well suited for our purposes.

« Last Edit: November 04, 2006, 08:09:40 AM by Len Silva »

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Offline DrivingMissLazy

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Re: Chaining up tag axle
« Reply #18 on: November 04, 2006, 08:53:44 AM »
The Eagle suburban was a 35 foot coach. All with the bogie axle were 40 foot.
Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body. But rather to skid in sideways, chocolate in one hand, a good Reisling in the other, body thoroughly used up, totally worn out and screaming:  WOO HOO, what a ride


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Re: Chaining up tag axle
« Reply #19 on: November 04, 2006, 01:57:37 PM »
Here are the pages from the MCI Maintenance Manual for the 96- A2, A3 and 102- A2, A3.

You need to remember that the wheel base on the 3 axle MCI's is measured not from center of the front axle to center of the tandems, (like a truck is), but from the center of the front axle to the center of the drive axle.

The wheel bases on on the 96A2 and 102A2 are longer because the drive axle has been placed where the tag axle on the 96A3 and 102A3 is. Thus the 2 axle coaches have a lager turning radius than the 3 axle coaches.

Also notice the vehicle weight and payload capacity.


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Re: Chaining up tag axle
« Reply #20 on: November 04, 2006, 02:01:51 PM »
And the second page:

Offline Jeremy

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Re: Chaining up tag axle
« Reply #21 on: November 06, 2006, 03:45:27 AM »
It so happens that when returning home from a long trip on saturday evening I had to wait for a short while only 1/4 mile from my house as the road was blocked by a big double-decker coach (a Scania I think) trying to do a 3-point turn (I live close to a motorway junction, and the coach had evidentally taken the wrong exit off the roundabout). Whilst watching the coach doing the manoevre I realised the Scania was fitted with a steerable third axle, which is something I had not seen before on a bus. Obviously truck trailers often have steerable axles, so I guess it's a no-brainer to put them on a bus as well - it's just that I'd never actually seen one before.

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