The Ulti Wheel Change Project

July 2012: After enjoying our Ultimate camper for 18 months or so I decided to change the wheels and tyres to match the tow vehicle (a Prado 120 series).  This was in mind from very soon after getting the Ulti, but was prompted by experiencing a shredded tyre (on the Prado) on a trip to Karijini in May 2012.  We only had the one spare on the Prado, so suddenly we were without a spare, and still with 60km or so to get to Tom Price.  Not quite white-knuckle territory, but definitely a bit uncomfortable.  Fortunately a tyre dealer in Tom Price sold Coopers and had the exact size I needed, so we were not held up for long at all.

This was the sight that moved this project up the priority list. Just after entering the unsealed road near Tom Price.  The time between realising something was wrong and hearing the terrible noises of bits of tyre flapping around could not have been more than 20 or 30 seconds.  But it was enough for the tyre to overheat to the point of total failure.  It even dislodged the right rear corner section of the plastic bumper - it was hanging by one fastener, but fortunately wasn't damaged beyond a few scratches.  I had to get some new fasteners, but it was easy to pin it back in place.

Don't know when the actual puncture happened - it could even have been back on the bitumen.

FlatTyre
This is how the Ulti looked when we bought it nearly two years ago.

Five-stud Landcruiser rims with big 265-width BF Goodrich tyres.
Ulti Before

I found three rims via Gumtree, to match the rims on our Prado. Ours is a Standard (or GX), with the 6-inch steel rims, now running 235-70R17 Cooper tyres.

They were a bit dirty and grotty, and I had always thought I'd like to paint them white, so decided to go the extra mile and strip them right back to bare metal.  I was very impressed at the effectiveness of paint stripper!

Stripping
The primer applied.  I used spray cans of paint for this exercise. Primed
And the first coat of white. Starting to look good. 05-White
I thought it would be a good idea to leave the final coat of white until after the tyres were on.  Turned out to be a good move.  Masked up here ready for the final spray.  The masking over the tyre is the stuff sold for house painting - masking tape with a strip of plastic attached. 06-Tyres On
Now it was time to attend to other mechanical bits and pieces.  This is the new 6-stud spare wheel bracket bolted into place.  The pinch bolts were incredibly tight, and it took a couple of applications of penetrating oil before I could move them to get the old bracket off. 07-Carrier
And with the spare in place, ready to go. 08-Spare On
Off with the old 5-stud brake drums.  I had changed the bearings myself not long after acquiring the Ulti, and was quite pleased with how they looked after 18 months or so.  A lot of the grease still seemed to be there, and both the bearings and stub axles looked to be in excellent condition.  I still put new bearings in though - they are cheap so it makes sense to replace them while everything is in pieces.  I used the blue Castrol boating grease (recommended somewhere on the Ulti forums). 09-Old Drum Off
Anointing the new bearings with grease.  All of the spaces and cavities in between and among the rollers should be filled. I used a wooden popstick to work it in there. 10-New Bearing
Tapping the seal in over the inner bearing.  They are a very tight fit and fairly fragile so it's easy to damage them. If a hammer is used to tap them in, something flat like a piece of wood spreads the force and reduces the risk of damage. 11-Insert Seal
Working some more grease into the cavity that will exist between the axle and the inner surface of the "tunnel" through the hub.  The syringe (from a hydroponic supply shop) worked quite well, but the grease can't be too cold, or it won't  flow enough to suck into the syringe from the tub. 12-Fill Cavity
Once everything was opened up the brake magnets could be inspected.  Note where the arrow points, the surface is worn to the point that the little dimples are no longer visible.  This is the indication that they should be replaced - the dimples are wear indicators.  Before removing them, I took this picture to the trailer parts shop for them to check and advise - I thought I was being clever, but apparently it is quite common nowadays. 12a-Brake Magnet
On with the new.  The new hubs are zinc-coated.  All that remains is to hammer on the little dome covers for the outer bearings.  They are also very tight, and caused a fair bit of bad language before they finally yielded! 13-New Drums

Standing on its new feet.  Yes, it looks a little skimpy compared to the original, but after a week we won't even notice.  I much prefer the security of car and camper providing spares for each other.

The overall tyre diameter is slightly less (maybe 30mm) than the original setup, which is fine, because the Ulti was slightly nose-down when towing. This will make it closer to level.

Now it just needs a test run to bed in all the rubbing surfaces, then a brake adjustment, and we will be good to hit the road again.

 14-Nearly There