Hi,
when planning my expedition camper (TGB13 based) the topic "tires" always comes to mind. Since I will modify the brakes to fit Toyota calipers and discs with newly machined hubs from, I will end up with Toyota lug pattern. New 37x12.5R17 tires will also require a little less offset than original, if there are to be used with snow chains for sure.
Finding wheels with large offset seems to be one hell of a problem, getting some manufactured to my specifications could be an option, but takes a lot of money. The question is: How much offset will those portals stand? Or: How low can I go? Are there any experiences with aftermarket wheels or rims of different offsets?
I have seen widened Volvo original rims, 2-3 inches added on the outside, which would bring the offset down to values as low as 30 to 55mm. How strong are the wheel bearings and/or the general construction of the portal/bearings in general? Are they prone to break earlier when tinkering with offsets, is the whole design rather immune to such changes? I'd be looking for first hand experiences there, favourably with fairely heavy expedition trucks, not super-light ralley or trophy trucks.
W/o modifying any rims, I might be able to legally aquire 8x17" rims with Offset 35mm. Half an inch to narrow according to most tire manufacturers specifications, but that might be overlooked upon technical inspection. Anyway, we're looking at 70mm of spacers compared to the original Volvo wheel here!
Example of 70mm spacers with original rims (tires 36"):
Option could be, to widen the rims afterwards to the inside... maybe add one or 2 inches. That could bring the offset into the 60mm range. Very expensive procedure of unknown effect.
Small background info: I want the rear camper box to be 2m wide to enable the construction of the bed purpendicular to the driving direction, thus creating a lot of free space for comfort and living. Therefore I'd not be too unhappy aber wider track.
My problem is simply: I need some kind of reliable vehicle, can't push importat bits and pieces to the extreme. Is the portal/bearing section prone to damages somehow?
Thanx for your thoughts,
.martin