Thread: Engineering compliance for larger tyres based on vehicles with the same axel

There is no other vehicle that uses the same axles as the D2 .

I think the D2 is not the ideal vehicle to "Engineer"

Originally Posted by goingbush

There is no other vehicle that uses the same axles as the D2 .

I think the D2 is not the ideal vehicle to "Engineer"

Hmmmm... I'm starting to feel like you are correct. Bill suggested he had done it previously based on the Defenders. I can get him paperwork for him, but at a cost yet to be determined by him.

The Defender comes out with tyres approximately 2" larger than the Discovery 2 from standard. Here in Tassie you can lift your Defender up by 2" and increase the tyres sizes up to 33.5" without any engineering being needed, meanwhile the D2 with it's more advanced handling (thanks to the ACE) stays low... Maybe it would just be easier to fit a Defender tyre placard...

Anways, I have contacted an Engineering Signatory here in Tasmania that comes highly recommended from my girlfriends dad (he assisted him in gaining Special Interest Registration for his race car with a roll cage, gutted interior, battery in the boot, etc.), so I'll wait and see what he says about it all. It's a public holiday ehre today, so will probably be a little while...

Defenders are 32" standard tyre so helps a bit there with respect to mods before engineering compliance.

Originally Posted by twr7cx

Hmmmm... I'm starting to feel like you are correct. Bill suggested he had done it previously based on the Defenders. I can get him paperwork for him, but at a cost yet to be determined by him.

The Defender comes out with tyres approximately 2" larger than the Discovery 2 from standard. Here in Tassie you can lift your Defender up by 2" and increase the tyres sizes up to 33.5" without any engineering being needed, meanwhile the D2 with it's more advanced handling (thanks to the ACE) stays low... Maybe it would just be easier to fit a Defender tyre placard...

Anways, I have contacted an Engineering Signatory here in Tasmania that comes highly recommended from my girlfriends dad (he assisted him in gaining Special Interest Registration for his race car with a roll cage, gutted interior, battery in the boot, etc.), so I'll wait and see what he says about it all. It's a public holiday ehre today, so will probably be a little while...

Your engineer is probably thinking of D1s. D1s and 90's have substantively the same axles. Hence a logical argument there.

D2 axles on the other hand are quite different to D1 and defender axles.

The only real difference is the ends, the housing is pretty much the same. Just has open knuckles instead of the swivel balls. These are welded the same way, by rotary friction. They were also fitted with 18's on the same housing so you could go the +mm size on to the 18" dimensions.

Apart from that, I like the thinking in fitting the different placard.

Thats like saying the diff housing off a Patrol is basically the same as its painted black...

There are very few similarities apart from the mounting face for the diff centre.

Almost everything else is different.

Knuckles instead of swivel ball.
Knuckes are welded on.
ball is a bolted connection.
Width is different, overall and bare housing.
totally different hub / wheel bearing and brake setup
different suspension mounts
Not only that, but also Watts linkage on the rear as opposed to an A frame.
Different shock mounting set up on the front.
Anti roll bar mounting position the other side of the housings.
not fully floating.
Different axles and cv's

There is no way you can argue they are almost the same...

Originally Posted by clubagreenie

The only real difference is the ends, the housing is pretty much the same. Just has open knuckles instead of the swivel balls. These are welded the same way, by rotary friction. They were also fitted with 18's on the same housing so you could go the +mm size on to the 18" dimensions.

The D2 came with three tyre options - the 235/70R16, 255/55R18 and 255/65R16. The 255/65R16 is actually the largest diameter of the three, but there's not a lot of difference between all three of them.

Originally Posted by Psimpson7

Thats like saying the diff housing off a Patrol is basically the same as its painted black...

There are very few similarities apart from the mounting face for the diff centre.

Almost everything else is different.

Knuckles instead of swivel ball.
Knuckes are welded on. Flanges for swivels are welded by
ball is a bolted connection. ----same method
Width is different, overall and bare housing. ???
totally different hub / wheel bearing and brake setup
different suspension mounts Both Radius Arms, ok different but...
Not only that, but also Watts linkage on the rear as opposed to an A frame.
Different shock mounting set up on the front. Every coil rover I've seen -----------------------------------------has shocks inside coils on front.
Anti roll bar mounting position the other side of the housings. And?? There's ACE vs Non ACE on D2's
not fully floating. Non load bearing parts
Different axles and cv's As above.

There is no way you can argue they are almost the same...

Question was based on housing, remove the bracketry and apart from track you can fit D1etc housings to D2's