WHEELBASE REDUCTION

[TEXASHUNTER]

Boy, do I need some advice on this. I own a 2005 Mahindra
5500 2WD. The outside back tires show to be 77" to the edges.
My trailor is 77." It is a 3500 twin axle rated at 7000lbs. They all
seem to be 77" wide. I know it's under rated for the tractor--but
I want to reduce the width of the outside back wheels. No one
seems to be able to tell me exactly how much it can be taken in.
Also, can I do it or is it a dealer job. HELP PLEASE!

 

[Hangfire]

I don't have book in front of me but I think you can reduce wheel base to 72"
or less. This job requires ability to safely jack up and block both sides of tractor and to safely move the very heavy wheels. If your tires are filled I would not even think about trying myself.

Think of the wheel as bowl shaped. If the inside of the bowl is bolted to the axle, then you have the narrowest wheel configuration. If the bottom of the bowl is bolted to the axle then you have the widest configuration. In addition to changing the wheels, the rim of the tire can be bolted on the inside or outside of the wheel which also narrows or widens a few inches. In my case I was able to swap the two rears on a 6500 FWD and go from narrowest to just shy of widest with no changing of the rims. I would not try this myself again without more help and a hoist or something similar to assist. If took me a few hours to switch my wheels and I am certain that it was not too safe.

Hope this is clearer than it seems.

 

[TEXASHUNTER]

Okay, one more time for an idiot. I think I got the wheel
thing-turn the wheel either in or out-now tell me about
that rim thing again. Thanks.

 

[Hangfire]

Checked the Mahindra site, they list width as 77.4", this may be as narrow as will go. Also, we are talking about reducing width, wheelbase will be the measurement between front and rear wheels.

 

[TEXASHUNTER]

Yes, I do mean the width. Sorry.

 

[Hangfire]

At least on my 6500, the rim bolts onto the wheel which is concave. You can bolt the rim on the inside or the outside of the wheel. The rim has what looks like built in spacers that are probably 2" (from memory) on one side of the rim. Therefore, rim on inside versus rim on outside of wheel base changes width by more than the thickness of the metal the wheel is made of. Hard to describe without looking at the rims. I think technically, because you could take the tire off the rim and flip the rim Mahindra gives 6 or 8 possible widths.

 

[Hangfire]

If you flip the rim without taking tire off, your ags will be running backwards, so with out changing tires you have 4 possible widths. Concave in or out and rims on inside or outside of the flange of concave.

 

[TEXASHUNTER]

Thanks, you have me started.

 

[rback33]

If you flip the rim without taking tire off, your ags will be running backwards, so with out changing tires you have 4 possible widths. Concave in or out and rims on inside or outside of the flange of concave.

Hey.. I was going to point out the tread issues u got all the fun..lol My guess is that they are as narrow as they'll go if 77 is listed on the site. Narrowest is usually the spec listed.

 

[bindian]

Uh....when you swap concave for convex rims and tires............you also swap sides to keep the tread going forward. Unless you are doing all your work pushing (as in reverse) a boxblade, as in piling up brush and logs to burn.
My 6520 has 5 different tread widths, with the max. (in the Ops manual) being 75.4 inches. Which is not correct as my trailer is 83 inches wide and I have about 3 inches to spare.
hugs, Brandi

 

[TEXASHUNTER]

Hey.. I was going to point out the tread issues u got all the fun..lol My guess is that they are as narrow as they'll go if 77 is listed on the site. Narrowest is usually the spec listed.

I called Mahindra and the guy there said it was possible to take it
in from the 77" mark. But, he did not know how much in. I hope the
77" is not completely in-or I'm stuck.

 

[VistanTN]

My Manual covers 4500 to 6500 4WD, but I suspect the rear axle/rims/hubs are the same for the 2WD. It shows four possible combinations of rim setting (dish out or dish in), rim setting (mounts out or in), and attachment of hub to rim (hub at outer edge or hub toward center). Since there are two choices for each, there should be 8 combinations, but I suspect the 4 innermost run into the fenders. Working from the narrowest shown to the widest shown, they are:
1. Hub dished in, mounts in, hub attached to outer edge of rim 63.66" track
2. Hub dished out, mounts out, hub attached to outer edge of rim 68.09" track
3. Hub dished out, mounts in, hub attached on center side of rim 71.66" track
4. Hub dished out, mounts in, hub attached on outer edge of rim 76.09" track

Now, I don't know if they use the tire centerline as the track measurement -- possible and if they do, the outside to outside measue of the rear wheels/tires would be a full tire width wider.

Just to confirm, if you turn the tire around (to change the rim mount position, you do have to switch tem side to side to keep the traction bar direction correct.

If you want diagrams, send me a private e-mail and I'll draw some up for you (the ones in the manual are pretty awful).

 

[VistanTN]

Got some "bad" news for you. I checked my 6500 this morning and the track measurements listed in the manual ARE center to center of tire tread, not outside to outside. Based on that and the manual listed positions and numbers, the narrowest outside to outside dimension you can acheive is 82.16". The three narrower (than that) mathematically "possible" settings do have fender interference problems. All this is based on a tire thickness of 18.5" which might be reduced a little by higher inflation, but NOT enough for a 77" wide trailer. Sorry

 

[RedRiver]

77" is the tightest you are going to get it. @ 77" you only have 2" or so of clearance from inside the fenders.

 

[George2615]

Sounds like a wider trailer is in order. Something with 82" between the fenders.