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 [emoji15]

[veebs]

Really... this..... again [emoji15]

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[tonguewink]

[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

[PerthDisco]

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[tonguewink]

Why, why why does LR have to be teacher's pet then.

Likewise on that basis when fitting Compomotive 18"s it is defeating the manufacturers design no more/less than changing back to the 2.7D discs and calipers? What is the exact law that is being broken?

Agree - not a D3/D4 thing.

Moral of the story - don't get anywhere near a LC200 with a tow as it is a wonder with their inferior braking system they can stop at all let alone swerve to miss you.

[scarry]

Why, why why does LR have to be teacher's pet then.

Likewise on that basis when fitting Compomotive 18"s it is defeating the manufacturers design no more/less than changing back to the 2.7D discs and calipers? What is the exact law that is being broken?

Agree - not a D3/D4 thing.

Moral of the story - don't get anywhere near a LC200 with a tow as it is a wonder with their inferior braking system they can stop at all let alone swerve to miss you.

Not really,if you use the 18" size as per placard,very little changes,and is legal.

Changing brake rotors to a smaller size, and calipers, is a massive change which may mean the vehicle has to be plated by a suitably qualified vehicle modifier,or it may be illegal.

[justinc]

Yes no logical reason to reduce brake size. the 2.7 brakes are just ok if using in a 'normal' duty cycle. It is certainly a welcome upgrade in the 3.0 models. I stuck the 4.2SC 360mm brembo fronts on my td6 as i tow a decent size van and car trailers etc from time to time. Can never have too big brakes 😎. Saying that i can still fit 19" rims, which so far haven't been any problem.

Jc

[Graeme]

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.
The early alloy 3.0 rear calipers had blobs of metal protruding out the ends for no apparent reason other than to block the fitment of 18" rims but were later replaced with the D3's smaller, strictly functional cast iron calipers that allow 18" rims to fit (same as the V8 D3), presumably because the alloy calipers caused squealing in reverse when dusty.

The 2 centre ribs on the front calipers protrude further out than the end 2 ribs. If a person is prepared to make the modification, the centre hump of these 2 ribs can be reduced a couple of mm to allow 18" rims to fit. IMO this is a better proposition these days than fitting 2.7 brakes to allow 17" rims due to the range of 18" tyres now available and that LR 18" rims now fit the rear.

[cjc_td5]

The early alloy 3.0 rear calipers had blobs of metal protruding out the ends for no apparent reason other than to block the fitment of 18" rims but were later replaced with the D3's smaller, strictly functional cast iron calipers that allow 18" rims to fit (same as the V8 D3), presumably because the alloy calipers caused squealing in reverse when dusty.

The 2 centre ribs on the front calipers protrude further out than the end 2 ribs. If a person is prepared to make the modification, the centre hump of these 2 ribs can be reduced a couple of mm to allow 18" rims to fit. IMO this is a better proposition these days than fitting 2.7 brakes to allow 17" rims due to the range of 18" tyres now available and that LR 18" rims now fit the rear.

When I measured it up I calculated that I had to remove about 10mm from the ribs on the front calipers to fit the OEM 18" wheels I have. The estimated shave is shaded RED in the attachment. My engineer would not sign off on this modification.

Chris

[Graeme]

The end ribs are untouched and only 3-4mm off the highest points of the centre 2 ribs is all that is required.

[Graeme]

If I can't find sufficiently durable, quieter tyres for my L322's 20" rims then I'll fit the front discs and slightly shaved calipers from the more powerful, faster accelerating, same GVM and towing capacity 5.0 L322 of the same year which uses the same caliper as the 3.0 D4, noting that the D3/D4 LR 18" rim already fits the rear.

[Grentarc]

The end ribs are untouched and only 3-4mm off the highest points of the centre 2 ribs is all that is required.
The end ribs actually do need about 1mm taken off, the centre two need about 2 -3 mm taken off, and the trailing edge of the front of the main body (leading up to the ribs) needs about 0.5mm taken off to provide enough clearance for a standard LR 18" wheel to turn without fouling.

[PerthDisco]

So the question remains if those ribs are there solely to exclude 18" wheels from fitting? The amount of metal to be removed would not seem critical.

[Grentarc]

So the question remains if those ribs are there solely to exclude 18" wheels from fitting? The amount of metal to be removed would seem critical.
What i think may have haplened was they got the CAD file of the 2.7 caliper, then scaled the drawing x% to cope with larger discs and didn't care that 18" didn't fit anymore.

[SBD4]

What i think may have haplened was they got the CAD file of the 2.7 caliper, then scaled the drawing x% to cope with larger discs and didn't care that 18" didn't fit anymore.

Justin, I see you have 19" rims on yours. If memory serves me right, I think Graeme installed the 2.7 calipers, are they still in place or have you gone back to 3.0Ltr calipers?

[Grentarc]

Justin, I see you have 19" rims on yours. If memory serves me right, I think Graeme installed the 2.7 calipers, are they still in place or have you gone back to 3.0Ltr calipers?
I have gone back to the 3.0 brakes, but now have a set of LR 18" that also fit

The entire 2.7 brake package was installed - discs, caliper carriers and calipers. As I did not get the 17" BMW rims with the D4 when I bought it, I decided there was no point keeping the smaller brakes

[Graeme]

You'd better keep them locked up now that I know I can make them fit my RR!

[PerthDisco]

I meant to say would not seem a critical amount of metal needing to be removed

[SBD4]

I have gone back to the 3.0 brakes, but now have a set of LR 18" that also fit

The entire 2.7 brake package was installed - discs, caliper carriers and calipers. As I did not get the 17" BMW rims with the D4 when I bought it, I decided there was no point keeping the smaller brakes

Have you noticed much difference in braking capability between the two? I guess you will have needed to push them to make the differences apparent.

[Graeme]

Ah, that makes more sense!

[Grentarc]

Why did you go back and have you noticed much difference in braking capability between the two? I guess you will have needed to push them to make the differences apparent.
I went back as there was no need for the smaller brakes if I didn't have smaller wheels, so we decided to put to original brakes back on, and if I went to 17s later I could always put the 2.7 brakes back on. I have since decided to go with some LR 18" wheels, as they don't require the rear brakes to be changed and the front only needed the smallest amount of polishing to fit.

I have pushed them both, and there has not been a noticeable difference at all going from the 2.7 to the 3.0 brakes, but not with anything in tow.

[SBD4]

You'd better keep them locked up now that I know I can make them fit my RR!

I'd imagine most people who know about your ingenuity Graeme, would feel very nervous if they found you admiring any particular part of their vehicle as they may well find it transplanted to yours in a jiffy! Watch out indeed Justin!

[Grentarc]

I'd imagine most people who know about your ingenuity Graeme, would feel very nervous if they found you admiring any particular part of their vehicle as they may well find it transplanted to yours in a jiffy! Watch out indeed Justin!
Now I will have to check the boxes still have the rims in them every time I get home [emoji53]

[Graeme]

I used the 3.0 brakes for nearly 45K kms before fitting the 2.7s and apart from the vehicle trying to throw me through the windscreen the first time the 2.7 brakes were used, I never considered the brakes to be different. However I only towed a 1.2T van and only country driving where braking is mostly optional.

[Graeme]

I'd imagine most people who know about your ingenuity Graeme, would feel very nervous if they found you admiring any particular part of their vehicle as they may well find it transplanted to yours in a jiffy! Watch out indeed Justin!

He's lucky that his e-diff uses a different housing.

[SBD4]

He's lucky that his e-diff uses a different housing.

Sounds like you're eyeing off the D4 as working parts bin...[wink11]

[Graeme]

His 19" rims fit the RR - had them on instead of the rubber band 20" before going up a size or 2.

[PerthDisco]

I used the 3.0 brakes for nearly 45K kms before fitting the 2.7s and apart from the vehicle trying to throw me through the windscreen the first time the 2.7 brakes were used, I never considered the brakes to be different. However I only towed a 1.2T van and only country driving where braking is mostly optional.

Great information. I think we have pushed this topic along really well now. My takeaways are;

Little real-world braking difference (which seems to make sense)
Only front brakes need modification

I'd just love to know if it was in fact LRs intention to block the 18" wheels to be fitted as would seem no engineering challenge to make suitably sized calipers for the 3.0D larger discs. A good project manager would have told the bright-spark engineer to go back to the drawing board on any other day.

[veebs]

Agreed - seems like such a simple engineering change to remove what some consider a 'weakness' - ie, the inability to fit 18" OEM wheels on a 3.0.

I would put this in a similar category to the rear plastic trailer plug cover - where a better solution must surely be possible with just a LITTLE more thought...

[Graeme]

I'd just love to know if it was in fact LRs intention to block the 18" wheels to be fittedThe original rear calipers with their blobs of metal hanging out the ends were obviously made to prevent 18" rim fitment.

Correction: The 3.0 rear brackets have the blobs hanging out the ends which do not interfere with 18" rims. The alloy calipers themselves are too bulky, possibly needing more metal than cast iron to have the same strength but also possibly to prevent 18" rims..

[kreecha]

Noting we have many great minds here, and some with more time than others...

Has this solution been investigated;
Custom front brake calipers from the likes of Harrop or Wilwood (etc)

My idea may have immediate flaws as I myself have not spent alot of time considering it or researching it.

Cheers,
Adam

[cjc_td5]

Noting we have many great minds here, and some with more time than others...

Has this solution been investigated;
Custom front brake calipers from the likes of Harrop or Wilwood (etc)

My idea may have immediate flaws as I myself have not spent alot of time considering it or researching it.

Cheers,
Adam
Dunno about the more time bit, but here goes...
I have looked at this path. Looked at Willwood & AP Racing calipers. I wanted to keep the factory rotor. Key issue is clearance to the wheel spokes as the wheels are such a big + offset. Diameter wise it comes down to less than 5mm clearance. If only the rotor was 350dia (vs 360mm), all would fit well....

[kreecha]

Dunno about the more time bit, but here goes...
I have looked at this path. Looked at Willwood & AP Racing calipers. I wanted to keep the factory rotor. Key issue is clearance to the wheel spokes as the wheels are such a big + offset. Diameter wise it comes down to less than 5mm clearance. If only the rotor was 350dia (vs 360mm), all would fit well....

CJC, Thanks for comment.
Did Wilwood or AP offer direct fit replacements?
Were further adaptations/changes required?
When you speak of less than 5mm clearance, is that with the Wilwood or AP calipers and the 360mm discs?
What was the clearance to wheel spokes?
What factory 18” wheels did you use to do the testing?

Cheers, Adam

[kreecha]

I just did some very quick googling. I am providing data here to offer others opportunity comment based upon this premise;
Change brakes and use LR wheels as an alternative to buying compomotive rims IF 18" tyres are desired.
Found this; Land Rover Discovery 4 / LR4 (09 up) Front Big Brake Kit (http://pbbrakes.com/land-rover-discovery-4-lr4-09-up-front-big-brake-kit.html)

Benefits;
Ability to fit factory 18” wheels, which look better (opinion) than compomotives,
6 or 8 piston calipers (to which the argument could be had – these calipers in theory should offer greater braking force, feel and modulation),
Top-hat disc design (to which the argument could be had - these discs in theory should dissipate heat more efficiently than factory).

Negatives (please expand if you feel the need to add comment);
Purchase price + freight,
Engineering requirement?
Unknown pad availability?
Fitment issues?
Legality?
Still have to buy LR rims after fitting brakes.
Brake pad availability and price.

I’d have to do a CBA to understand more about the change.
Also for Victorian LR addicts, (I will be moving to Vic L), if tyres only are changed they can be 50mm bigger. If wheels and tyres are changed (but are not factory – compomotive) then a 15mm maximum increase of tyre size is the law. (That is my understanding of VicRoads bulletins).

I’m interested to read comments from you all. Please flame as appropriate.
Cheers, Adam.

[Grentarc]

...
Engineering requirement?
...
Legality?
...
I’m interested to read comments from you all. Please flame as appropriate.
Cheers, Adam.

When fitting aftermarket brake packages, you still have to get it engineered as you are not fitting a factory brake package to the vehicle.

[kreecha]

When fitting aftermarket brake packages, you still have to get it engineered as you are not fitting a factory brake package to the vehicle.

Yes Justin, that is my understanding. Not everyone may agree, nor abide by the law in the pursuit of saving some $$

[cjc_td5]

Did Wilwood or AP offer direct fit replacements?
No, I was looking for low profile calipers from their range to match the D4 piston area, generally 4 or 6 pot calipers.

Were further adaptations/changes required?
All Willwood et al calipers require a bracket to be designed and fabricated to bolt to the hub mounting points.

When you speak of less than 5mm clearance, is that with the Wilwood or AP calipers and the 360mm discs?
Using the AP Racing calipers as an example, the caliper sits at 203mm radius, (i.e. 406mm diameter) on a 360mm rotor. The D4 18" wheels I have are 410mm inside wheel diameter.

What was the clearance to wheel spokes?
From memory approx 10mm.

What factory 18” wheels did you use to do the testing?
I have the attached wheels.

Chris



CJC, Thanks for comment.
Did Wilwood or AP offer direct fit replacements?
Were further adaptations/changes required?
When you speak of less than 5mm clearance, is that with the Wilwood or AP calipers and the 360mm discs?
What was the clearance to wheel spokes?
What factory 18” wheels did you use to do the testing?

Cheers, Adam