How big is too big? Tire size for (heavy) 1HZ Camper. (1 Viewer)

[Aidan Klimenko]

Hey there. I've done some searching have have found some good resources and info regarding tire size and R&P ratios but almost all of what I'm finding is for gas engines.

I'm new to this forum and I'm fairly new to my 2002 HZJ78 camper, which is pretty heavy and running the turboless 1HZ. The vehicle is built for long term overlanding and I'm using it as such. It's actually down in the mountains of Ecuador right now waiting for me to return to it once borders open back up. SO, altitude and big hills are a consideration.

I'm currently running 265/75/R16s (so 31.6") with 4.11 R&P. I believe the trans is stock gearing.

I'd like to jump up to 35" if I could to it without sacrificing much in terms of power and top speed.

Can anyone shed some insight on:

a) if it's a dumb idea (it's pretty much only for aesthetics).

b) what size R&P would be ideal for 35" tires on a diesel with overlanding in mind.

Thanks!

 

[roscoFJ73]

a) if it's a dumb idea (it's pretty much only for aesthetics).

For overlanding , 32 is the best IMO. Big tyres do give you a small advantage off-road, but the extra height makes them unstable in emergencies on the highway and long wheel base 7* series never had a lot of stability in the 1st place. I always carry 2 spares and carrying 2x 35" tyres and wheels is a lot of weight and extra room.
I think the 33's should be the maximum and even then you can feel the extra diameter working against the brakes.

 

[SNLC]

35’s are going to be super slow. You got 125hp at sea level when the engine was new. You have made it heavy.

You can re-gear but that will kill your top end speed and it won’t give you more power.

You can add a turbo but the 1HZ can die an early death from that, especially if not done right and overworked.

Your best bet in my opinion is to live with it or do an engine swap. You could go to 33’s and say 4.56 or 4.88’s but I would advise against that if you came to me to do the work.

Cheers

 

[serenity]

It’s also worthwhile considering what tyre size is common in the areas you frequent. If you need a replacement along the way it may be more difficult to source a 35.

I’d stick to a 265 or 285 as they are a common size and suit these vehicles well.

 

[David*BJ70]

You can/should also consider 255/85R16 but the availability and variety is not as common as a 265 or 285. Their narrowness makes them an excellent tire for an ovelanding rig

 

[GTSSportCoupe]

I'd recommend an e-rated heavy duty 235/85R16 (32" or so). Efficient and tough tire. And it's amazing where you can go with them when aired down and taking the right line. It's a common size in North America at least.

 

[roscoFJ73]

It’s also worthwhile considering what tyre size is common in the areas you frequent. If you need a replacement along the way it may be more difficult to source a 35.

I’d stick to a 265 or 285 as they are a common size and suit these vehicles well.

I blew 2x 33 on the way to Alice Springs from the WA side. At Yulara they wanted to sell me a complete new set of tyres. I made them put a tube in the 33 that wasnt too bad. Im sure they sabotaged it because it went flat overnight. They charged me $77 (2007) for tube and labour and were really pissed off I didnt want to pay for their overpriced s***ty tyres.
Tyre shops in Alice said it would be 4-5 days to get BFG 33s from Darwin
I ended up buying 2 x 16in split rims with new 235/80/16 tyres on them from a wrecker in Alice cheap and used them on the rear to get home, 2480klms away with 33s on the front. Looked a bit weird.

 

[tmarx]

Without a turbo and seeing that it is a heavy campervehicle, I suggest you stay with the size you have ... any larger will make it run even slower at much higher EGTs and destroy your fuel consumption.

 

[Silveredition]

I had a 1996 80 series with the 1hz and had always run 265/75r16 tyres. I decided I wanted to go to 285/75r16 (mainly due to looks). I drove it about 20km before I turned around, went back to the tyre shop and changed them back to 265’s....
It was horrible without towing anything, and could only imagine how much worse it would be towing my 5m boat.... up a slight hill it barely held speed...
In my opinion - the 265/75r16 size (width and diameter) is the best for a touring 1hz on standard gearing...
Just my opinion...

 

[David*BJ70]

Not an HZ story, but it is incredible how 1 ou 1.5 inch bigger can make a huge difference. On my ex-BJ70 (3.70 axle ratio), driving 265/75R16 and 31-10.5R15 was almost night and day ! (ok... dawn and day )

 

[Erwin]

I got me a 2001 78 2 years ago with 33" (285/75r16) BFG MUD. It has a 1HZ with turbo (fitted by PO) and IC (fitted by me). I did not like the handling, and especially not the MUD thread. Breaking on wet tarmac was especially frightening. So this year I went down to 32" ( 265/75/r16 ) AT. The handling is better, the transmission likes this size more. 35" will not be good. They are for hardcore offroading, not overlanding. And they will be unnecessary wide. Skinnier tires are better for all round use. And as said, you will have problems finding a replacement in the bush. 265/75/r16 is a common size, and the same diameter as 235/85-16 witch you will find anywhere.

Pic with 285/75-16