Brakes on 3.0 vs 2.7

[veebs]

Howdy all

I'll preface this question as something I have absolutely no intention of doing, nor would I ever advocate others to - legality and safety are both almost certainly compromised. Merely interested in the reasoning.

The 3.0 models as we know, have a larger brake pack than the 2.7 engines. I'm interested to know why this is the case? Why couldn't you, if having 18" (or even 17") wheels is desirable, not change the brake calipers and disks in a 3.0 to be the same as a 2.7?

The GVM/GCM of the cars are the same aren't they? Only the engine power really changes?

Sports cars sometimes have larger brakes for higher performance engine configurations, which I take to be so that the braking isn't compromised when 'racing'. Not sure that is a real consideration for a Disco though?

The Toyota LC 200 for example, is more powerful that the 3.0 SDV6 (200 vs 183 kw, 650 vs 600 Nm), and heavier (3350 vs 3240 kg GVM) but has smaller brakes (340mm vs 360mm on the fronts).

Don't get me wrong here - I much prefer what may be an over engineered braking system to one that has to work extra hard!

[shanegtr]

The D4 has a better terrain response system than the D3 so the bigger brakes make a difference to the traction control performance

[PerthDisco]

Great question that has been bashed around before.

Likewise, I cannot understand as old brakes were not bad and you are not pulling her down from 250km/h on Conrod Straight or towing any heavier weights.

The argument for TC seems similarly flawed as most times it is in action at very low speeds so the incremental gain from larger brakes is minimal IMHO. In any case why would they give you better TC at the expense of off-road unfriendly 19" and 20" tyre choice? Seems counter intuitive. My bet is on the TC gains being a software only change that could probably work equally well on a D3.

The best argument I have seen is that the D4 calipers have a rib cast into them that block the fitting of an 18" wheel (other than Compomotive) to pass the Moose swerving test on low profile rubber. Don't know why does not apply also to LC200.

That's why I think the techo gains in the D4 are generally to the detriment of what was a well sorted 'fit for purpose' package in the D3. Yes, yes, yes, the D4 has more power and 8 gears (more for emissions?) but the D3 was also upped to higher power levels.

I watched that 4X4 Australia 'Across the Bight' video last night and it was a bit sad to see the D4's getting bogged regularly (ok so did others) and chewing through tyres. The video almost indicated they had a bunch of Toyo support vehicles and a LR Factory Mechanic along to get them there.

The prosecution rests.

[veebs]

not sure it's a D3 vs D4 thing - I though the 2.7 D4s could take the smaller rims too? Also, my D4 has a 6 speed box

Was watching the bight video too - I simply assumed that the Toyota drivers were the cameramen, and so not filming whilst digging their own vehicles out!

[101RRS]

Noting that these cars are sold all around the world and speed limits in some countries may be higher than they are here, I would assume it is to match the higher performance of the hi spec 3.0 over the 2.7.

As you indicated the 2.7s and 3.0s are about the same weight and in some circumstances I can certainly get my 2.7 brakes to fade and this may not happen with a 3.0.

Garry

[Tombie]

Really... this..... again

[veebs]

Really... this..... again

Where is the existing thread on the same topic? I sure can't find it...

[shanegtr]

The best argument I have seen is that the D4 calipers have a rib cast into them that block the fitting of an 18" wheel (other than Compomotive) to pass the Moose swerving test on low profile rubber. Don't know why does not apply also to LC200.

You seen the current hilux and previous model moose swerve tests on you tube? I dont think Toyota really gives a rats arse about the test

[DiscoJeffster]

I'm clearly guessing but I feel this is likely a blend of marketing, design and capability. Marketing always says bigger is better, be it capacity of engine, KW, wheel inches, etc. Design will say the 19" is more aesthetic. Capability will say in their brake capability they could really do with more brakes for 3500kg towing capability and steep descents down mountains (as an example). All this combined to a decision to giving the 3.0L bigger brakes and mandating 19".
I'm sure they perform some form of analysis based on acceleration capability to braking capacity to set mine the correct size for most 80/20 cases which feeds this.
Anyhow. It is what it is!

[LandyAndy]

I sometimes get to tow our 2000lt diesel fuel trailer behind my work ute.After that you would appreciate the D4 brakes.Colarado/Rodeo brakes are very poor.
My D4 with fully loaded camper trailer brakes really well,no sign of fade either.
You only get 1 shot at stopping in the work ute.
Andrew