Better 70-Series brakes? (1 Viewer)

[Jonathan Hanson]

Now that our FZJ75 is in the states for a while, there are a few things I want to do to it, and high on the list is to improve the braking of its four-wheel-disc system. My first move will be to install DOT 4 or 5.1 brake fluid, semi-metallic pads, and possibly braided lines. However, the real improvement would come from installing larger-diameter or wider rotors. Installing multi-piston calipers by themselves is pointless. Drilled discs do nothing to reduce fade. Heavier stock-sized discs (for example, with extra cooling vanes) would also help. Does anyone know of an aftermarket source or a bolt-on Toyota swap to achieve this? My approach stems from an article I wrote on Overland Tech and Travel some time ago (here) about the myths of so-called high-performance aftermarket brake kits, many of which are no such thing. P.S. I really want to stay with 16-inch rims. Thanks for any experiences or direction.

 

[coldtaco]

If you haven’t done a search yet might be worth it. Lots been done on this topic. Seems the biggest improvements come from replacing the brake booster ( right word?) with one from other applications like from an 80 series or?

 

[Jonathan Hanson]

Thanks. I have done several searches, and the booster idea is intriguing, but all it can really do is improve response and feel (not that that's a bad thing). It won't shorten stopping distances or reduce fade. With our Troopy near GVWR I want stronger and more fade-resistant braking.

 

[Loober]

80 series booster and MC, along with removing LSPV and installing the manual proportioning valve made the brakes on my 70 work and feel like any modern car. Mine does have rear disc, which obviously is an improvement over older drum models. Not following on the brake fade, I doubt you are "racing" your 70 series to where you have a high cycle on the brakes causing them to overheat, "normal" braking should not be experiencing fading unless your existing system is not working properly. I would start there before looking into aftermarket options, which are usually worse then OEM.

 

[Hulsty]

As above, 80 series booster, I also bored out my master for larger pistons. Stock they have 4 piston calipers, best pads I found were QFM A1RM, after much abuse they just do not fade. Unfortunately no longer available. After those you would be looking at better rotors, past that moving to later model 70 series brakes which work with 16'' rims.

 

[divemedic]

Why do you feel vented and/or slotted rotors don’t improve fade resistance?

what driving situations are you experiencing brake fade?

The answers may reveal why you feel the above information isn’t relevant to your specific concern and can help with advice given.

 

[Jonathan Hanson]

Why do you feel vented and/or slotted rotors don’t improve fade resistance?

what driving situations are you experiencing brake fade?

The answers may reveal why you feel the above information isn’t relevant to your specific concern and can help with advice given.

Divemedic, if you read the article in the link I included in my first post, you'll understand my thoughts. The "vented" rotor you mentioned refers to the radial slots around the edge of most modern rotors—those most definitely help cooling. However, cross-drilled rotors actually do nothing for cooling/fade resistance as they reduce the mass of the rotor. It's the dirty secret of aftermarket brake rotors. Slots are designed for something entirely different: scraping the pad to eliminate or reduce glazing. The best way to reduce fade—beyond better fluid and pads—is to increase the diameter and/or width of the rotor to increase its thermal mass.

I'm concerned about fade in part because my wife and I participate in biological studies in the Sierra Madre in Mexico, and even with hyper-aware use of gearing I've experienced fade in several vehicles on 5,000-foot descents out of those ranges.

 

[divemedic]

I’m not seeing a link on my end in your first post.

high end drilled rotors are fine and do improve brake performace by design when used as intended (expelling trapped gases from the brake area). However, when high performance pads are also introduced the more aggressive compound will eat rotors faster (regardless of drill/slot or blanks. In all honesty, the best advice I can offer is:

ensure your brake system is performing correctly. I currently have Baer oe replacement rotors with project mu pads up front, OEM drums and shoes in back.

I guess my truck to be +6000 lbs when loaded and almost never touch my brakes off road. Only during city/paved roads in traffic never experienced fade. I plan on converting the rear to discs and using terrain tamer rotors and pads for towing performance.
You say you’re hyper aware of engine braking. I am not trying to be trite, but consider you’re technique may need refining. Keep in mind my optics are limited. Are the roads you’re on require higher speed due to traffic? Paved vs dirt? Are you in 4 or 2wd low or high range? Does your trans/engine overheat?

 

[Jonathan Hanson]

It appear my original link did not take, sorry! It should work now.

There are so many myths still circulating about brakes, it is difficult to distinguish fact from hype, which is why I did the research incorporated into the linked article. For example: Modern brake pads no longer outgas, which was the main reason for early adoption of cross-drilled discs. No longer necessary for that purpose, period. The only credible advantage to cross-drilled discs is a slightly enhanced initial bite in wet conditions. They don't cool the brakes and they don't reduce fade, according to about a half-dozen proper brake-system experts I either talked to directly or referenced.

I take no offense at your suggestion about my technique! However, I've been doing this a long time, I've taught driving skills for over a decade both privately and at events, most recently at the Overland Expo which my wife and I started. The descents we deal with are typically on pavement, very curvy, speeds of between 30-50 mph, with enough traffic that going more slowly would wind up annoying a bunch of drivers behind you. I've used vehicles on these trip ranging from our 2012 Tacoma and Four Wheel Camper to an FJ60 with a swapped International 3.0 turbodiesel. So I'm confident in predicting that the braking on our Troopy will be exercised strenuously when we take it down there.

This is why I'm asking about brake swaps that would give me either larger-diameter or wider discs without having to go up in wheel diameter. An earlier response mentioned later 70-Series brakes; I'll have to do some research to see if they are larger than those on the 1993 vehicles, and if they would fit with six-lug hubs. Thanks very much for the input!

 

[SNLC]

PZJ70: stock rear drums, all new though. New 70 booster and master. New 80-series calipers/rotors and pads up front. New rubber lines all around and a few new steel as well. LSPV gone and replaced with a proportioning valve.

The result: some of the best brakes and braking I have ever experienced in a Cruiser.

Cheers

 

[SHREDwagon]

Thanks for any experiences or direction.

Thinking your solution would have been easier to come by in Aus. There's a few companies that make kits for mine trucks over there. Hoppers Stoppers would be one to contact and discuss - assuming existing is 100%.
Delios rotors as well (no experience)

 

[red66toy]

@bjowett

 

[divemedic]

Reaching out to the Japanese market or your behalf. https://m.facebook.com/groups/257238977802499?view=permalink&id=1167819690077752

 

[Indestructible 47]

I think pdi (performance diesel intercoolers) of all people were selling a better booster for the 70. Might pay to check it out.

Get backing plate removal kits too, stops stones getting in and scraping the rotor.

Seems like you know what you want yourself and have a reasonable handle on it. I've had excellent results out of dba (disc brakes Australia) and decent pads with a brand new master cylinder (go genuine) and dual diaphragm booster as well. More of us guys in Aus are starting to use braided lines too.

Make sure that all parts are compatible with dot 4 or 5.1 fluid, I know Toyota didn't specify it.

 

[divemedic]

Guys in japan are recommending an exhaust brake kit and switch to dot 5.1 fluid.

Pacbrake:Exhaust Brakes

pacbrake.com

 

[FJBen]

Guys in japan are recommending an exhaust brake kit and switch to dot 5.1 fluid.

Pacbrake:Exhaust Brakes

pacbrake.com

PAC brakes are awesome. I've used one a few times. My mom's 2006 Dodge cummins has one, and coming down the mountain passes in Colorado you barely even have to touch the brakes if you don't want too.

I'm sure you mod one to fit, but you could also use one from an Isuzu NPR. You can find those things anywhere. Simple, just need vacuum and 2 wires for an on/off solenoid and you are good. Really cheap used a trucker salvage yard, or new is less that $500.

 

[divemedic]

Check these guys out too, they may have 6-lug kits. Heavy Duty Brake Upgrade | Gearing Dynamics

I too recommend the PAC stuff. Not from personal experience but my family does farm work and most of their work trucks have the kits. If you email PAC and provide them vehicle information they can get you the best kit/part for your needs. Another alternative that’s well reviewed in Australia and Japan is:

Exhaust Brake for small diesel vehicles | Gearing Dynamics

gearingdynamics.com.au

 

[Waikato Willy]

I stuck some Bi metallic race pads (QFM brand) in an old commodore years ago, they chewed out the rotors like my kids eating lollies for breakfast

tell you what though even when the fluid boiled out the master cylinder I still had a brake pedal even when the back brakes caught fire

 

[roscoFJ73]

I put new DBA rotors and pads all round on my 75 series ute a few years back. The brakes were so good they didnt need upgrading.

 

[Hulsty]

PZJ70: stock rear drums, all new though. New 70 booster and master. New 80-series calipers/rotors and pads up front. New rubber lines all around and a few new steel as well. LSPV gone and replaced with a proportioning valve.

The result: some of the best brakes and braking I have ever experienced in a Cruiser.

Cheers

How do you fit the 80 series brakes to a 70 front end ?