1985 Nissan 720 motorhome or datsun

[antho]

I am new and need some help, i bought a motorhome a year ago and want to upgrade to bigger tires and bigger rims. Wondering whats the maximum i can go without lift kit, its dually rims in the back thx

[datzenmike]

Bigger? If you mean taller I wouldn't, it will kill your acceleration and ability to maintain road speed, into the wind, up hills and passing... specially a camper that's basically as aerodynamic as a barn door.  Wider? You might get slightly wider but they are duals so they are going to crowd each other. Also they have to stay inside the wheel arch or the camper will rub the tires on bumps. Dual tires are for weight carrying not traction or looks. Keep or replace with what you have.

 

Contact wayno on here. He knows about dual axles and rims and what fits... https://ratsun.net/profile/5657-wayno/

[wayno]

I do not know a lot about Motorhomes but I suspect that an 85 Motorhome would have the C200 dually axle under it, I would use the stock size tires for mostly one reason, the rims are a set distance apart, you do not want the tires too close to each other as heat can become an issue, Motorhomes are not light and the tires can spread apart like a half filled tire does and if they touch each other they can get hot and fail.

 

 

[antho]

Thank you guys, i saw a user that went with bigger but it was on a toyota oddyssey motorhome, cant find the user no more,  all i want is to go just à bit higher as mine are 14inch

[Stinky]

What sort of transmission do you have?

 

Do you have any idea of your axle ratio?

 

What size tire do you have on it now?

[datzenmike]

The HD or Cab/Chassis option for '82s only came with a four speed standard transmission.

[antho]

I have 14 inch rims, 185r14c are my back tirés,  would like to go maybe 15 to be à bit higher is it possible, if somebody with more knowledge can tell me whats my options are thx

 

Manual tranny 5 speed dont know my ratio

[Stinky]

Those are itty-bitty tires.

 

You go to 15s and the issue of changing your overall axle ratio (when you factor in the change in circumference of the tire) becomes a major issue.

 

Your 4.banger pushes that thing around because it turns a lot of rpm.

 

The long and short of it...it wont work.  That is to big of a change.

 

Imho

[Ranman72]

look at your existing tire size diameter then look for a 15 inch tire with a close diameter 

it will be lower profile but can still be almost the same diameter 

https://tirecalculator.com/185r14-tires

https://tirecalculator.com/195-65r15-tires

 

you can play with this till you find a combo that works 

even a 16 inch wheel can still have a smaller diameter then the 14 inch 

[datzenmike]

Five speed may have been swapped in. They were standard on the later '83 and up because of the larger Z24 engine which has more torque to pull that load at highway speeds.

 

Look on the passenger side inner fender, below the hood hinge, for the engine tag.

 

 

Type or Model will begin with the letter E if Camper/Heavy duty or Cab/Chassis. This option comes with a much lower (numerically higher) differential gearing that allows the engine to rev slightly higher than a regular 2wd. The engine is thus making more power to pull a heavy camper. Don't mess with the over all gearing by going to taller tires.

 

Lower right corner is the axle. CA46 is a C-200 and 4.625 ratio on this truck but most are 4.375.