Changing 17.5" Tires to 16"

[LJ-TJ]

Well I did search for the change down and didn't really see an answer. The side walls on the new bago 17.5 is starting to get cracks. The old bago that burnt had new 16" tires on it. I've been thinking of changing them out onto the new bago. Anybody got any thoughts or ideas on this GOOD or BAD. The rims on the burnt out bago the 16s are dodge dimpled rims and do fit over or around the disc brakes.

[DaveVA78Chieftain]

As long as they will fit the only thing to worry about is weight rating.  Do the 16" meet your weight needs?

Dave

[LJ-TJ]

Good question Hm? I'll have to go out and check tomorrow. There on a 1975 21 footer. I bought them brand new to replace the one's that were on it so I just assumed that they would be fine. Silly me figured that it the weren't the lads at the tire store were I bought them would have said something as up here they are a very reputable Tire Store. I was kind a wondering about increased gas mileage and speedometer error. N:(

[rustyescott1]

tj i've done this on one of my mh's before. had no major problems. only major differance is about  a 1/2 inche outside diam. rusty

[JDxeper]

TJ
I changed the 78 Brave from 8R17.5 to 235/85/16R load range E(3045 llbs).  They were close in height and diameter so no adjustment was needed in the speedometer.

[DaveVA78Chieftain]

TJ,
It was because I knew others had done this successfully is why I said only concern is Load weight range.  If your good there you are good to go.  This works on a M300 with single disc caliper version.  However M400 chassis with dual disc caliper (like mine) it will not because of caliper size.

Dave

[LJ-TJ]

Hey Guys all is good I'll go out and read the tires to be sure and post what I come up with . If I didn't want to know I wouldn't have asked and you lads have never steered me wrong yet.  Just bought a 50'X50' barn as well as another 50'x40 that has to be dismantled before we head to Jim's. So....lots of work ahead and still want to get some projects done on the bago yet.

[LJ-TJ]

OK! There Michelin Lt 225/75 R16. Load Rang E  Does that work?

[JDxeper]

The load range "E" will do fine.

[DaveVA78Chieftain]

Well lets see,
According to http://www.michelinrvtires.com/michelinrv/tires-retreads/load-inflation-tables.jsp, a Lt 225/75 R16 tire
Single = 2680 LBS at 80 PSI
Dual = 2470 LBS at 80 PSI
So,
Front = 2 x 2680 = 5360
Rear - 4 x 2470 = 9880

So max possible weight these tires can support = 15,240

Now, depending on wheel base, the max GVW for your chassis is either
10,200lbs (104" WB) or
11,000lbs (125" WB)

11,000 is well within the tires 15,240 limit

For reference, the MH manual says 300 Series chassis used load Range C up through 75.

Now what the load range table is telling you is that you can run a lower pressure which will give you a little softer ride.

Do you have any clue what max pressure the 16" rims are rated at?
Reason I ask is the original Dodge 17.5 rims are only rated at 60lbs with a 70lb optional rating.  Going above the rim limit can result in rim degradation (I had one rim start leaking a few years ago; non-repairable).

Hope that all makes sense
Dave

[LJ-TJ]

Yep! Makes lots of cents which means we're good to go. Thanks a million. You guys been great helping get the old girl squared away. Learned a lot of neat stuff along the way.Thanks

[LJ-TJ]

Well near killed myself today but I changed from 17.5's to 16 inch tires. Haven't taken her out for a test drive yet but tomorrow should be a good time.

[DaveVA78Chieftain]

Looking good TJ.  I bet LJ is smiling to!   

[ClydesdaleKevin]

Beautiful!   

Kev

[JDxeper]

Good show, TJ!  Y!

[DonD]

She looks even more beautiful than before!!!!