Thread: Speedo and Tyre Size

The one I am aware of is sold at Ashcroft in the UK
Ashcroft Transmissions

Originally Posted by Mk1_Oz

My lad has just bought his first 4WD, a 2003 Disco 2 TD5 HSE and is well happy. Should be - a great car if looked after and will keep him occupied for life. Welcome


The previous owner removed the standard rims and tyres (we got those thrown in for free!) and replaced them with much larger tyres (I forget the size). Predictably the speedo no longer reads correctly.


I have not investigated where the speedo gets its signal from although suspect it is linked into the ABS system and wheel sensors.


Is there a method/black box to permanently correct the speedo in these cars or will he have to rely on either a GPS unit or liquid paper marks?

Yes - two items. Speedo Adapters (C6100-4 speedo correction unit) Hunter DI Spares. phone number 0413813698. Email: hunterdispares@yahoo.com.au
(It's the Truspeed that has the 2 way switch)
I have the C6100 and very happy, even without the two way option. I did hear some had problems with the Truspeed.

Also recommend a Nanocom Evo if he plans to keep the car. Best diagnostics and with an instrument mode. And an adjustable speedo to boot, but the highlight is an accurate coolant temp - the LR version is useless unless you like to be told after you have cooked the engine.
Also get a low coolant alarm from Dave's shop on here - cheap insurance.


(Terrible turning circle - assume that is caused by the large tyres....)

No - comes as standard although you may be able to slightly adjust the front wheel stops.

There is an Australian device that should fix the problem

Official home page of the Yellow Box Speedo Recalibrator

I have one in my truck (not LR but same technology) and for my purposes its brilliant. Ive added a switch & can switch back & forward btw standard & modified speedo on the fly .

If your son gets serious about playing in the dirt as well as using the car as a daily driver he'll end up swapping wheels frequently. I've found that a Head up Display GPS unit (about $100 on the 'net) by far the easiest way to compensate for different tyre sizes...

Originally Posted by GazMann

The one I am aware of is sold at Ashcroft in the UK
Ashcroft Transmissions

This is for Defenders only, they use a transducer on the transfer box D2 uses ABS wheel sensors.

Like Gavin said the Hunter Di Spares C6100 works. I have one on my D2.

Some more info here http://www.aulro.com/afvb/discovery-...tion-unit.html

Cheers all.

I have a D3 so was thinking of buying one of the OBD2 readers/computers. Not sure which one. Need one that does both cars and all systems.

Originally Posted by aussearcher

If your son gets serious about playing in the dirt as well as using the car as a daily driver he'll end up swapping wheels frequently. I've found that a Head up Display GPS unit (about $100 on the 'net) by far the easiest way to compensate for different tyre sizes...

X2
Nick