Abel Villesca
Explorer
That's a great looking rig Bluewater! :sombrero:
Australian touring vehicle
- Thread starter The BN Guy
- Start date
Bluewater Australia
Observer
Some of the pics were taken at Wedge Island just north of Perth, some at Yeagerup on the south-west corner down south, but the rock pic was taken somewhere between Bremer Bay and Hopetoun, on the south coast east of Albany...
engineer, that's the first time I've had somebody volunteer that there is a better vehicle than an OKA on corrugations, and by your location, you would know; what is it? People often ask what the OKA is like on corrugations; and I don't know if they believe me or not, but usually all you can do in this OKA is hear the fact that you're on corrugations, you can't really feel it.
engineer, that's the first time I've had somebody volunteer that there is a better vehicle than an OKA on corrugations, and by your location, you would know; what is it? People often ask what the OKA is like on corrugations; and I don't know if they believe me or not, but usually all you can do in this OKA is hear the fact that you're on corrugations, you can't really feel it.
RHINO
Expedition Leader
it all depends how you show it off,, good onya mate !! that how ya say it ?
engineer
Adventurer
"engineer scratches head"
whatcharterboat
Supporting Sponsor, Overland Certified OC0018
I was waiting for that. Hahahahhahahahahah. Followed by Lololololol.
Mate, I've seen a few running around here on 19.5 wheels. Do you know what tyres they are running?? What do they come from the factory with?
The one I saw up at Inskip had Michelin XDE+2 but he wasn't happy with them. Not suitable at all for a 4x4 and he was looking for a better alternative.
I've already posted these pics but it's a very cool looking setup , heh? From the Gold Coast.
whatcharterboat
Supporting Sponsor, Overland Certified OC0018
Hi Alan , These rims obviously weren't supplied by OKA. IIRC The owner told me he paid $750 each for them. Made on the Gold Coast. Not Titans. Really thick centres but only MIGed and not submerged arc welded. Still more suited to the weight of the truck.
IIRC it was 5.5 ton with the camper. Not 100% sure of that. The camper looked very light but there was a lot of tanks, and the steel tray, etc.
IIRC it was 5.5 ton with the camper. Not 100% sure of that. The camper looked very light but there was a lot of tanks, and the steel tray, etc.
Bluewater Australia
Observer
Tyres have been a bit of a love/hate relationship for me. The following was written for the Oka Owners Group newsletter a while ago. The earliest OKAs had 16" wheels, but most later ones had 19.5". As one wag put it, given that most OKAs ended up being sold as tour buses, the fact that 19.5s weren't as good off-road was not so bad, because when they got bogged, they had 13 people on board to get out and push! ...
A little history first: our LT OKA was purchased with the standard 19.5” wheels, fitted with Michelin XZY 285/70s. This was a fairly popular setup on late 90s OKAs, and while they serve the purpose, they are really nothing special. The steel wheels are diabolically heavy, and looked dead ordinary. We had them sandblasted and powdercoated a few years back, which made them look better and clean easier, but nothing was going to make them lighter.
However, the real problem was the tyres. The 19.5” size is uncommon, and while not unobtainable, the choice is very limited. Picking one up when you need one at short notice is unlikely to happen. Worse still, they’re not designed for off-roading; reducing tyre pressure to get flotation over sand required some pretty low pressures at times, and 19.5” truck tyres were never designed to be trundling around at 40psi, let alone 14psi. We tried to stick to 65psi on the highway and 25psi on sand, but it was a telling tale as we destroyed tyres one after another – almost one every serious trip, a nerve-wracking scenario when you know you have no chance of finding a 19.5” tyre anywhere within 3000km.
The final straw was having yet another tyre disintegrate on the highway, and trying to get it replaced back in Perth only to be presented with a ‘new’ tyre that, by the date code, was already two years old; so to all intents, 1/3 of its way through its useful life, and of course at full quid.
So, after an inordinate amount of measuring, internet trawling, saving up and finally committing, I ordered a set of 16 x 10 Pro Comp forged alloy wheels, and Pro Comp Xtreme A/T 38.5/14.50R16 tyres.
A lot of the internet research was to do with finding wheels that were appropriate to the load-carrying requirements. Cast alloys are out; they have to be forged. The wheels I chose are from www.procomptires.com ; with the required 8x6.5 stud pattern, they’re rated to carry 3500lbs a corner; or a little over three tonnes each axle. I think all the various styles have the same load rating with that stud pattern.
I chose 16 x 10 for the maximum off-road ability within the realms of not necessitating body or suspension modifications; there are plenty of options. The standard 4.5” backspacing (very common amongst aftermarket wheels) was going to work fine with the OKA.
On to tyres, and the same company looked the goods with their Xtreme A/Ts. Despite being fairly huge, this tyre has a directional tread pattern, so they should be quiet, and good in the wet. All my measuring said I could fit in the 38.5” diameter ones – just – and they should be the best off-road. Their load rating was a whisker more than the wheels, so no problem there. Once again, there are options; smaller diameter tyres give more gearing power and are more easily matched for outside diameter if you need to buy something in a remote location. But I was on a roll now.
Once they landed, came the big test: were my measurements right, and was it going to be driveable?
The wheels clear the brakes by about 2mm. Scary close, but no problem. The backspacing was good, and the rears clear all around the outside with room to spare. The fronts just brush the LT’s splash panels in front of the tyres (XTs don’t have those panels) at full lock, just enough to take the paint off, nothing to bother about really; but eventually, we will have a sheet metal maestro modify them just to keep it absolutely legal. Remember these tyres are much bigger than standard; most would not go to this extreme.
Width-wise, I was keen on flotation, and certainly pushed the limits. After nearly two years of contentedly driving around with them poking out the sides a bit (and they really did look cool like that!), I thought I should do the right thing, so we bought four new flares from OKA (to save the panel beater a bit of work) and got them fitted up 30mm further out than the originals. The rears already had enough ‘extra’ to do that with, and fortunately for me OKA had a set of wider-than-standard cab flares in stock, so it was an easy job on the front too.
While the spare could still be squeezed under the rear at this size, it was a squeeze; touching the springs both sides. So that went up on the roof, with a little removable winch & derrick setup to get it on and off. So far, it hasn’t had to come off. On big trips we still stick one of the old 19.5s under the rear for a second spare.
Driving: no problem. They have been powder-balanced (powder within the assembly, no external weights), something I had never come across before, and the balance is perfect. They’re quiet, soft-riding (I’ve been using 45psi as a highway pressure) and great off road. On sand at below 15psi, they’re at home, bagging down beautifully.
The pic is of the originals and the new. The new make the 19.5s look like they’re running low profiles! The weight difference is significant: the original 19.5 steel wheel with a well-worn 285 tyre weighs 67kg; the alloy 16 with the 355 tyre and twice as much tread depth weighs 55kg.
We’ve had one puncture so far; a massive steel nail (used for pinning down a traffic-counting strip) that went straight through the tread, and resulted in a slow enough leak to allow a prompt drive to the nearest tyre repairer; where it was easily fixed.
We’ve also fitted up a wireless Tyre Pressure Monitoring System, which seems to be a good thing.
A little history first: our LT OKA was purchased with the standard 19.5” wheels, fitted with Michelin XZY 285/70s. This was a fairly popular setup on late 90s OKAs, and while they serve the purpose, they are really nothing special. The steel wheels are diabolically heavy, and looked dead ordinary. We had them sandblasted and powdercoated a few years back, which made them look better and clean easier, but nothing was going to make them lighter.
However, the real problem was the tyres. The 19.5” size is uncommon, and while not unobtainable, the choice is very limited. Picking one up when you need one at short notice is unlikely to happen. Worse still, they’re not designed for off-roading; reducing tyre pressure to get flotation over sand required some pretty low pressures at times, and 19.5” truck tyres were never designed to be trundling around at 40psi, let alone 14psi. We tried to stick to 65psi on the highway and 25psi on sand, but it was a telling tale as we destroyed tyres one after another – almost one every serious trip, a nerve-wracking scenario when you know you have no chance of finding a 19.5” tyre anywhere within 3000km.
The final straw was having yet another tyre disintegrate on the highway, and trying to get it replaced back in Perth only to be presented with a ‘new’ tyre that, by the date code, was already two years old; so to all intents, 1/3 of its way through its useful life, and of course at full quid.
So, after an inordinate amount of measuring, internet trawling, saving up and finally committing, I ordered a set of 16 x 10 Pro Comp forged alloy wheels, and Pro Comp Xtreme A/T 38.5/14.50R16 tyres.
A lot of the internet research was to do with finding wheels that were appropriate to the load-carrying requirements. Cast alloys are out; they have to be forged. The wheels I chose are from www.procomptires.com ; with the required 8x6.5 stud pattern, they’re rated to carry 3500lbs a corner; or a little over three tonnes each axle. I think all the various styles have the same load rating with that stud pattern.
I chose 16 x 10 for the maximum off-road ability within the realms of not necessitating body or suspension modifications; there are plenty of options. The standard 4.5” backspacing (very common amongst aftermarket wheels) was going to work fine with the OKA.
On to tyres, and the same company looked the goods with their Xtreme A/Ts. Despite being fairly huge, this tyre has a directional tread pattern, so they should be quiet, and good in the wet. All my measuring said I could fit in the 38.5” diameter ones – just – and they should be the best off-road. Their load rating was a whisker more than the wheels, so no problem there. Once again, there are options; smaller diameter tyres give more gearing power and are more easily matched for outside diameter if you need to buy something in a remote location. But I was on a roll now.
Once they landed, came the big test: were my measurements right, and was it going to be driveable?
The wheels clear the brakes by about 2mm. Scary close, but no problem. The backspacing was good, and the rears clear all around the outside with room to spare. The fronts just brush the LT’s splash panels in front of the tyres (XTs don’t have those panels) at full lock, just enough to take the paint off, nothing to bother about really; but eventually, we will have a sheet metal maestro modify them just to keep it absolutely legal. Remember these tyres are much bigger than standard; most would not go to this extreme.
Width-wise, I was keen on flotation, and certainly pushed the limits. After nearly two years of contentedly driving around with them poking out the sides a bit (and they really did look cool like that!), I thought I should do the right thing, so we bought four new flares from OKA (to save the panel beater a bit of work) and got them fitted up 30mm further out than the originals. The rears already had enough ‘extra’ to do that with, and fortunately for me OKA had a set of wider-than-standard cab flares in stock, so it was an easy job on the front too.
While the spare could still be squeezed under the rear at this size, it was a squeeze; touching the springs both sides. So that went up on the roof, with a little removable winch & derrick setup to get it on and off. So far, it hasn’t had to come off. On big trips we still stick one of the old 19.5s under the rear for a second spare.
Driving: no problem. They have been powder-balanced (powder within the assembly, no external weights), something I had never come across before, and the balance is perfect. They’re quiet, soft-riding (I’ve been using 45psi as a highway pressure) and great off road. On sand at below 15psi, they’re at home, bagging down beautifully.
The pic is of the originals and the new. The new make the 19.5s look like they’re running low profiles! The weight difference is significant: the original 19.5 steel wheel with a well-worn 285 tyre weighs 67kg; the alloy 16 with the 355 tyre and twice as much tread depth weighs 55kg.
We’ve had one puncture so far; a massive steel nail (used for pinning down a traffic-counting strip) that went straight through the tread, and resulted in a slow enough leak to allow a prompt drive to the nearest tyre repairer; where it was easily fixed.
We’ve also fitted up a wireless Tyre Pressure Monitoring System, which seems to be a good thing.
Bluewater Australia
Observer
I found that one just now on the Owners Group site, but they don't have recent info on there. The wheels are aftermarket as you say; the pic on the OG site has it with black wheels, and given that it's #023 (yes really, the 23rd OKA ever made) it would have had 16" rims originally. It started out as a motorhome, but was converted to the aluminum tray, slide-on camper setup.
Very neat and very loved by the looks.
engineer
Adventurer
I seem to remember the Australian Getaway 4x4 Fraser island buses trialing the 19.5" on Canters. They sank one from memory, and removed them as a result. They were a full bodied canter done by NC&B. Weird looking things...
I love the look of the new OKA's with the 19.5s, They were alright on Cape York from memory, I think Oz had them. Warnsies trucks had them as well, but he ended up going back to 825/16. I know that's what Oz run on thier canters, we are on 235/85 16 at the moment. They give better ratios for the hill climbs at Daintree and Kuranda, rev like crap at 100k's though. I've found it makes no difference to fuel economy, large or small tyre, pressures will cost you though.
Warnsies truck with 825's
I love the look of the new OKA's with the 19.5s, They were alright on Cape York from memory, I think Oz had them. Warnsies trucks had them as well, but he ended up going back to 825/16. I know that's what Oz run on thier canters, we are on 235/85 16 at the moment. They give better ratios for the hill climbs at Daintree and Kuranda, rev like crap at 100k's though. I've found it makes no difference to fuel economy, large or small tyre, pressures will cost you though.
Warnsies truck with 825's
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whatcharterboat
Supporting Sponsor, Overland Certified OC0018
Yeah. Actually I drove one for Getaway some years back. Only as a short term fill in driver. This one had an aftermarket turbo and IIRC was back on 16" XZL's. I remember hitting a washout pretty hard in it and gt a few groans from the guys in thew back. Bet you'd know all about that.
Also I remember the gear linkages weren't too good either but the turbo on the old 4.2 was a hoot. Sorry for the hijak.
Blue Water, really appreciate the comments about your tyre selection. Well justified. What weight is your OKA or did I miss that?
Bluewater Australia
Observer
I've never weighed it but theoretically 3.8 tonnes bare, 4.5 tonnes with a usual load on. So the way things go, probably around five tonnes.
