Friday, 19 July 2024

Brake Options for JIMNY XL (JC74) 5 Door | Brake Pads and Discs

This article is not about big brake kits but it is about options available retaining the OEM caliper and rotor diameter of the Jimny XL JC74 or the Jimny JB74.
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The 3 Door Jimny JB74 (K15B) and the 5 Door Jimny JC74 (K15B) have a lot of parts in common, the chassis from the front to where the transfer case sits and then from the rear radial arm mounts till the tail end of the chassis it is identical between the 3 door and the 5 door. The difference is an additional section of about a foot in length and a new cross member in the extended part in between.

Similarly the cabin from the nose till about the front seats are identical in floor layout and cabin layout except the shorter front doors and thus the placement of B pillar. The the custom fit front floor mats of the 3 door Jimny is a perfect fit in the 5 door floor edge to edge. Powertrain, transmission and wheels are all the same. They are twins sharing lot of components but front brakes are not on that list.

Suzuki used a 10mm thick 290mm diameter solid front disc for the JB74 3 door version but for the JC74 5 door version they used a 17mm thick 287mm diameter ventilated disc. The brake calipers are also different between these two models with the JC74 calipers having wider gap to accommodate the thicker brake discs. The brake pads are also not interchangeable between the JB and JC calipers.

There is a complaint of brake judder in the Jimny when applying brakes from higher speeds and whilst repeated braking. Many have reported this in the Indian Jimny groups and is an universally reported niggle, myself included. Brake judder is caused by 1) either brake disc warping or developing hotspots and or 2) uneven transfer of friction pad material on to the disc caused due to hot spotting at high temperatures.

The text from Monster Sport website listing their JB74 upgrade brake discs is copied below. So it is understood that the OE solid discs of JB74 are also not upto scratch and Suzuki most probably upgraded the fronts to vented in the 5 door hoping to mitigate the issue.

"Brake Jadder is also the cry of Gymney.
In situations where hard braking is repeatedly due to the installation of high-performance brake pads or winding driving, normal brake rotors can cause heat distortion and cause brake jaders.
The Monster Sport brake rotors have been given an optimal heat treatment (hardened) that dramatically improves abrasion resistance, heat resistance and reduces heat distortion. Recommended for those who suffer from brake jaders."
(sic)

To tackle this some 5 door owners are using the JB74 upgrade slotted brake discs in their JC74. Not an ideal solution as you go further down you shall understand why. Whilst some 5 door owners are just upgrading the brake pads and keeping their factory brake discs. This is a sound option. Some have imported the JB74 upgrade brake pads from Japan and elsewhere and have been disappointed.

Suzuki/Maruti Suzuki when they added more mass and length to the JB74 to make the JC74 5 door Jimny they also changed the front braking system completely. The brake calipers, the discs and the brake pads are all different and not interchangeable (except for the brake discs, but not ideal as you will learn below). The brake pads are not interchangeable between these two vehicles either, because calipers are different. The calipers are different because the discs are thicker. The brake discs are different because Suzuki consider this an upgrade over the JB74 solid brake discs expecting the ventilated brakes to run cooler increasing life and decrease fade.

The origins of the 5 door Jimny XL JC74 braking system can be traced to the 3rd generation Jimny JB53 with the Renault K9K 1.5L turbo Diesel engine. The JB53 inherited the upgraded vented brakes the origins of which can be traced to the Vitara/Escudo (TD01W/early TL52W) whilst the petrol powered JB23, JB33 and JB43 continued with solid brakes. Ventilated brakes are designed to run cooler than solid discs. To take the heavier K9K Diesel power plant few critical components were beefed up in the JB53; amongst which one is the vented front brakes and the other the strengthened front axle housing.

Which brake pads fit?

Some vendors have already figured out the fitment and have been selling the pads in Jimny circles but they have not let out the details in public, obviously due to the fact that they wouldn't be able to sell as many pads if the information is out. The brake pad part numbers wouldn't be shared to those who had asked for it, and even paying customers receive brake pads in boxes with no part numbers on the box or the pads. So I took this as a fun challenge to figure out the fitment, for both brake pads and brake discs and thus now we have options.

Brake Pads FMSI ID: D556, D807
  1. EBC DP979 Ultimax2 (NAO, confirmed as GG)
  2. EBC DP6979 Greenstuff
  3. EBC DP4979R Yellowstuff
  4. Bosch BP556 (Semi Metallic)
  5. Bosch BE556 (Semi Metallic)
  6. Bosch BC556 (Ceramic, Confirmed as FF) 
  7. Brembo P79 008
  8. Brembo P79 008N (NAO)
  9. Dixcel 371038-EC (NAO, µ Min 0.35, Avg 0.41, Max 0.50)
  10. Dixcel 371038-M (NAO, µ Min 0.39, Avg 0.40, Max 0.52)
  11. Dixcel X-371038 (Semi Metallic, µ Min 0.57, Avg 0.60, Max 0.68)
  12. DBA DB1266SS Street
  13. ADVICS SN567P
  14. Akebono AN370WK
  15. AC Delco 14D556CHF1
There are too many brake pads to list and some of the known names I did not mention are Bendix, Raybestos, Wagner, Ferodo etc. Some of these specific part nos are infact "Made in India" (AC Delco and Bendix) as per the Country of Origin provided. In USofA look up '98 Chevrolet Tracker 4 door to find matching brake pads. You can search with the FMSI ID D556 which will yield manufacturer cross reference for several OEM and aftermarket pads. For my friends in Australia since this model year Suzuki Vitara/Escudo was sold there you can find brake options locally.

But do your research and do your homework because none of these brake pads and actually "listed" for the Jimny 5 door aka Jimny XL aka JC74.

Brembo

EBC

ADVICS

DIXCEL

Note on Brake Friction Coefficient µ and DOT Codes

All street brake pads sold in the United States is required to show the brake friction coefficient as a two letter code, for example FE, FF, GG, GF etc. The first letter indicates the friction at low operating temperature 93C to 204C and the second letter indicates the friction at higher temperature 149C to 343C.

The coefficient of friction (µ) codes (SAE J866) assigned to the letter is as given below. A pad with GF rating would have high initial bite when cold and reduced bite friction) when hot and a pad with GG rating would exhibit high friction when cold as well as hot. The friction code gives the user an indication on how a particular brake pad behaves but is not absolute.
  1. D = 0.15µ to 0.25µ
  2. E = 0.25µ to 0.35µ
  3. F = 0.35µ to 0.45µ
  4. G = 0.45µ to 0.55µ
  5. H = > 0.55µ
  6. Z = Not Classified
The brake pad friction materials contribute to the coefficient of friction and the overall performance. Most options we have for Jimny are - 1) Non Asbestos Organic (NAO), 2) Semi-Metallic and 3) Ceramic - each having their own pros and cons.

I bought Bosch BC556 brake pads (from overseas) which are ceramic and are not too expensive. I will keep the blog updated on how these perform as we go. Couple of photos of the actual brake pad are given below.




Alongwith the above Bosch brake pads I also made the purchase of the EBC Ultimax 2 from another vendor overseas, although both were ordered together the EBC arrived late. But I am very glad that the ultimax2 turned out to be GG rated "as advertised". The Bosch BC556 were advertised as GG but it turned out to be FF. 





Hope it does, as advertised! ;-)

Which Brake Disc/Rotor?

Skimming the brake rotor on a brake lathe is a process familiar to most? That is an option to get the runout corrected by shaving material off the friction face before junking the rotors, provided the rotor meets minimum thickness after this.

OEM rotors are junk when new combined with the brake pads that come stock on the Jimny. The brake judder could also be a "pad" problem if a quality aftermarket brake pad is combined with a new (important) OE rotor might just fix it. OE discs are cheap and a pair cost less than a set of aftermarket brake pads!

That said aftermarket brake discs could be better by build and metallurgy. Research and do your homework before purchasing any of the options below or finding alternatives based on the information available below. Because none of these are actually "listed" for the Jimny 5 door aka the Jimny XL aka JC74.

Brake Discs 287mm Diameter x 17mm Thick Ventilated Center Bore 108.3mm
  1. Brembo prime 09.C220.10 OE Replacement

There is a dearth of availability of the particular spec brake disc, i.e., the vented 287mm x 17mm disc for 108mm hub in the aftermarket. This is most probably due to the fact that 287mm x 17mm for 108mm hub size was only used for the 3rd generation Jimny 1.5TD from 2005 till 2018. Where as the same disc (287mm x 17mm) for the 107mm hub was used in older 3rd gen Diesel Jimnyies until 2005 and in the Vitara/Escudo/Tracker I mentioned about earlier in this article.

Edit: 02/08/2024 There are few more options to add on to the list here of the OE upgrade type. These are from TarOx and as per the specifications on TarOx website the discs are 287mm x 17mm suitable for 108mm hub.
  1. TarOx 2928 F2000 - Long curved grooves (OE Upgrade)
  2. TarOx 2928 G88 - 40 long straight end to end grooves (OE Upgrade)
  3. TarOx 2928 SJ - Cross drilled and slotted (OE Upgrade)
  4. TarOx 2928 C83 - Short straight grooves (OE Upgrade)
  5. TarOx 2928 D95 - Cross drilled (OE Upgrade)
  6. TarOx 2928 Zero - Plain (OE Upgrade)

3-Door JB74 Solid Brake Disc for 5-Door Jimny XL JC74?

I have mentioned that there are people who are using 290mm x 10mm solid discs in the Jimny 5 Door with stock brake calipers. The factory fitment for the 5 Door is 287mm x 17mm vented option and the caliper is wider to fit the 17mm brake discs. I would not combine the two, it is asking for brake failure.

If you wish to pursue the 290mm x 10mm solid brake rotor some of the options are listed below and if you go down this path my suggestion is to do it properly and use the JB74 brake calipers and the brake pads to go with these JB74 calipers.

If you use the 3door Jimny JB74 10mm brake discs in the 5 door Jimny XL JC74 with its stock brake caliper it would probable feel okay when the brake pads and the rotors are still new because there is enough meat on the pad and on the rotor. But it is not correct you are risking it!
  1. Brake caliper piston will need to push further out than it would with 17mm discs,
  2. The caliper will need to slide further in on the carrier sliding pins than it would on the 17mm disc,
  3. As brake pads and rotor wear out the pads could shift out of its seat in the caliper carrier due to the larger available gap between disc and carrier.
  4. Or worse the caliper piston pushes out further than its intended limit causing piston boot failure or more catastrophically a brake failure if the piston travels past the seal inside the caliper.
  5. The permissible minimum thickness of the 10mm discs is 8mm which is its service life. Try to imagine a 9mm or 8mm disc in a caliper with its gap specified for 17mm disc with minimum permissible thickness of 15mm.
Why would anyone would want to risk a total brake failure seeking out remedial measures for brake judder. Brake judder always > No brakes!

If you wish to use a solid rotor club it with its correct brake calipers, both solid and vented have their pros and cons. Select what works for you but use correct caliper. The part number of Jimny JB74 brake caliper assembly including caliper carrier is 55100-78R00-999 (or 55100-78R01-999), the latter is probably an updated part. The JB74 calipers are not handed are common for both sides.

Brake Discs 290mm Diameter x 10mm Thick Solid Center Bore 108.3mm
  1. Brembo prime 08B30410 OE Replacement
  2. DBA DBA578 OE Replacement
  3. DBA DBA587S Slotted
  4. Dixcel 3714043S OE Replacement & Upgrade
  5. Monster Sport 431300-5200M Upgrade
  6. Power brake AT339 Upgrade

If you are going this route, i.e., 290mm solids, there are a lot more options than what is listed above in both OE replacement type and upgrade types. With the information above you should be able to find a suitable option that fit your budget and needs.

107MM Hub Brake Discs for the 108mm Hub JB74/JC74?

These options would not fit the JB74 or JC74 hub without processing. On the forums I did read about someone who machined the center bore to 108.26mm to fit the 108mm hub. I just happened to notice that there are a few more upgrade type options available for this rotor, not limited to the options listed below. All the important measurements such as rotor including diameter, thickness, rotor hat height, PCD, bolt hole diameter etc. are the same.

Vented Disc 287mm x 17mm
  1. Brembo prime 09.6859.10 OE Type
  2. DBA DBA514 OE Type
  3. DBA T2 DBA514S Upgrade Slotted

Solid Disc 290mm x 10mm
  1. Brembo prime 08.5266.10 OE Type
  2. DBA DBA513 OE
  3. DBA T2 DBA513S Upgrade Slotted

I included the 107mm hub rotor options in the article just because it has been done and needed that covered. I then striked out the text because it is not recommended, but I wanted to bring forth that information to you. Without machining the rotor will not fit the 4th gen. If the machining is not perfect you will have more problems than you had hoped to solve. All name brand brake discs are balanced so any additional machining could throw that off.

5-Door Jimny XL JC74 Vented Brake Disc for 3-Door Jimny JB74?

Would it be worthwhile? It is a question that I cannot answer as we don't get the 3 door Jimny here and I cannot comment on its braking system in comparison with the 5 door. It is possible to replace the solid disc brake system of the JB74 with the JC74 vented disc system. The calipers on the JC74 are handed with different parts for LHS and RHS. For the swap you need 1) RHS and LHS brake calipers, 2) Caliper carriers, 3) 287mm x 17mm brake discs and 4) Brake pads. Maruti Suzuki part numbers for the 5 door Jimny XL JC74 brake caliper assembly including carrier are 55102M80T00 and 55101M80T00 for LHS and RHS respectively.

Kingpin Pre-load Adjustment

Some folks shimmed the kingpins and increased the preload on their new 5 doors to fix brake judder. This is treating the symptom rather than cause. With increased kingpin pre-load the swivel joint gets tighter it resists movement and the steering also gets tighter. A worn out kingpin or incorrectly set low kingpin preload would result in "death wobble" without ever needing to touch the brakes. If its the kingpin you will feel that on the steering wheel even if you do not touch the brakes, with or without steering damper which the 4th gen has from factory. If it shakes only when you are on the brakes get the rotor and pads inspected.
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The Warped Brake Disc And Other Myths Of The Braking System

  1. Myth #1:Brake judder and vibration is caused by discs that have been warped from excessive heat.
  2. Myth #2:Racing brake discs are made from steel.
  3. Myth #3:A soft brake pedal is the result of pad fade.
  4. Myth #4:Boiled brake fluid will be serviceable after it cools.
  5. Myth #5:Because they are non-hygroscopic silicon based brake fluids are suitable for use in high performance cars.
  6. Myth #6:The brake fluid reservoir should be topped up during routine service.
I did not write that, the above is by none other than Carrol Smith who has authored several books related to engineering applied in motorsports. If the headlines got your attention you need to read the complete article here.
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