Brake Pads for Overweight Tacoma

tjalward

Observer
Why SO narrow?? 235 is so much narrower than a stock tire even, doesn't make sense to me with a heavy truck. You will need to inflate them way higher than you would otherwise want, to support the weight, but then it is not much air volume to compress and absorb bumps... Even if you are into the pizza cutters (which are arguably better on a stock weight truck) on a heavy truck wouldn't you rather not have to inflate so much and have some comfort come from the tires too?

E rated is a given with that much on the back end, unless you wanted to inflate them way up and don't deflate or go offroad much. I tried a 35x10.5 Kenda Klever R/T on my truck, Load range D, and had to inflate way more than I wanted to carry the load. When you air down some it gets really squishy and not well controlled. Moved to a true 35x12.5 E rated tire, and wow, what a better difference for me in control, air pressure needed in a given condition, and traction. Granted I have to clearance a little more, but that is with 35, not 33.

My suggestion is to go with a 285 tire, your mileage is already bad, not gonna change much and it will support your load way better without over board on the pounds per square inch of the tire to pavement (note: not the psi in the tire). But if you are going to the 17", then a 255 80r17 is a better choice than a 235... IMO


of course actual measurements vary by manufacturer
 

jsnow

Adventurer
There are a lot of Overland shops installing these brakes with great success. I run them on my 1st gen Tundra and it went from sketchy to awesome with just adding these. I know several Tacoma owners running these, and the increase in braking power in pretty amazing. They are also designed to work with your factory brake booster/master cylinder, so it is truly a bolt on.

X-Line 4x4 Big Brake Kit (Stage-1) (powerbrakeglobal.com)
 

tjalward

Observer
There are a lot of Overland shops installing these brakes with great success. I run them on my 1st gen Tundra and it went from sketchy to awesome with just adding these. I know several Tacoma owners running these, and the increase in braking power in pretty amazing. They are also designed to work with your factory brake booster/master cylinder, so it is truly a bolt on.

X-Line 4x4 Big Brake Kit (Stage-1) (powerbrakeglobal.com)
I have to take some issue with this. Your tundra master size isn't the same as a tacoma is it? How many mm is it? And saying the kit is designed for your factory master isn't saying much... they are a 6 piston caliper with an adapter to our spindles. The master we have is different if it is vacuum boosted or electronic vs a Tundra. If it was designed for our trucks specifically, for the vacuum booster version, it would have piston area equivalent to 4 46mm pistons. Anything outside of that is not "designed" for our trucks, it is an adaptation that is changing the hydraulic advantage in one way or the other and has trade offs. Intended or adapted to a specific truck should also specify which trucks IMO.

Simple hydraulics are F=A*P, so long as the volume is supplied... but we don't have a system with unlimited volume like a hydraulic pump does.
I can tell you with certainty, that when you put larger pistons in the calipers with no other mods it will make the pedal more mushy than it was simply from the fact that it has to be pushed farther to deliver the fluid volume required by the larger calipers. That has impact on the rear brakes too. Some people hate this, some don't mind it.

What I'm not saying is that the kit you reference won't work or won't be better. Just about anything beats stock brakes with a heavy truck. But there are lots of examples on TW where people moved to BBK in front and had other problems including a miserable pedal feel. IMO, the thing that helps, is the later model Tundra booster and master, which is a larger bore master (on its own would make braking require more pedal pressure), but the dual diaphragm booster that bolts to it is a HUGE benefit to both front and rear brakes.
 

wicked1

Member
Why SO narrow??
The truck came w/ these tires. Previous owner says because of bad fuel mileage.. He said it helped. (had 285/75r16's before). I like them because personally, I haven't had any problem w/ them in a lot of rough conditions.. including deep snow and soft sand where others were getting stuck.
But.. I Just looked at the inflation difference between 285's and my 235's, and yeah... Big difference. The ride would definitely be better. 9 lbs heavier per tire, though. And an inch taller. And I have to choose new wheels.. Probably worth it, though. Maybe I'd do a 275/70r17..
Thanks for mentioning the inflation difference between the different sizes.. I hadn't thought about that, and I definitely want a lower inflation.
 
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jsnow

Adventurer
I have to take some issue with this. Your tundra master size isn't the same as a tacoma is it? How many mm is it? And saying the kit is designed for your factory master isn't saying much... they are a 6 piston caliper with an adapter to our spindles. The master we have is different if it is vacuum boosted or electronic vs a Tundra. If it was designed for our trucks specifically, for the vacuum booster version, it would have piston area equivalent to 4 46mm pistons. Anything outside of that is not "designed" for our trucks, it is an adaptation that is changing the hydraulic advantage in one way or the other and has trade offs. Intended or adapted to a specific truck should also specify which trucks IMO.

Simple hydraulics are F=A*P, so long as the volume is supplied... but we don't have a system with unlimited volume like a hydraulic pump does.
I can tell you with certainty, that when you put larger pistons in the calipers with no other mods it will make the pedal more mushy than it was simply from the fact that it has to be pushed farther to deliver the fluid volume required by the larger calipers. That has impact on the rear brakes too. Some people hate this, some don't mind it.

What I'm not saying is that the kit you reference won't work or won't be better. Just about anything beats stock brakes with a heavy truck. But there are lots of examples on TW where people moved to BBK in front and had other problems including a miserable pedal feel. IMO, the thing that helps, is the later model Tundra booster and master, which is a larger bore master (on its own would make braking require more pedal pressure), but the dual diaphragm booster that bolts to it is a HUGE benefit to both front and rear brakes.

They have Tacoma specific kits. From what I remember they take the size of your master cylinder and design the caliper to work with the stock system. I can tell you from my personal experience that it firmed up my pedal, and with a 7,000lb Tundra it stops right now. I will inquire about how they design the calipers, and report back because I don't remember if they adjust the size of the pistons, or not. Stand by!
 
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jsnow

Adventurer
Here is the reply I got from Powerbrake for those of you interested.

With our background in the building of race car brake systems we would usually decide on the caliper hydraulic ratios for a race car by taking a number of factors into account, one being the master cylinder size and volume. Besides front/rear balance we needed to ensure the master cylinder has sufficient capacity to supply the calipers, but also that the driver has ideal brake pedal effort and modulation. This is mainly because the race car, and its brake system, was built from the ground up with no basis to begin with. With a road going 4x4 application we take a far simpler approach. Since the vehicle already has a working brake system we mainly consider the OEM front brake caliper piston area. In the case of both the Tundra Gen 1 and the Tacoma it uses 4 x 45.5mm pistons per front caliper. We would match this piston area, but with 6-pistons to within a percentage or two. It will thus comfortably work within the OEM master cylinder/booster setup since the near same size OEM caliper piston area worked with that OEM master cylinder/booster setup. We do however follow that up with full software simulation and extensive on car testing to determine that factors such as front/rear balance, brake performance, pedal effort and modulation etc. are within our expected design parameters. In some rare instances we have found that the OEM hydraulic ratio is not ideal and we select a different caliper piston ratio to OEM in order to rectify this (older Toyota Landcruisers for instance), but still ensuring pedal feel and modulation remains satisfactory
 

nickw

Adventurer
OK, as an owner of a 8,000 pound (when fully fully loaded for long camp trip with no resupply) tacoma that can lock up the tires on pavement, I can provide some insight from my trials and tribulations with a heavy taco. And I won't debate or argue with anyone on what I should have done, why it is so heavy, whether I should have a different truck, etc. It is what it is.

A few things that I didn't see yet - do you have a vacuum booster or the electronic booster found on TRDOR and some other models? That makes a difference. Huge difference in your options.

I have TRD sport. Vacuum booster. I started small, pad upgrade back when I was in the 6500lb fully loaded range. Sucked, downright scary in a panic stop. I tried a few sets of pads and rotors, no real difference. Although, I can tell you with confidence, the best pads I've run are the EBC orange extra duty. They are specific for heavy trucks, 4wd, larger tires, etc. With the sport rotors they made a big difference, but I never ran those in stock size (read below). I have never tried, nor will I ever pay, for the BBK stuff that is out there... way too expensive and not easy for consumable parts, etc. Truck continued to get heavier and heavier with upgrades and gear, suspension and reinforcements for the weight, cause more weight, etc... On the heaviest outing I've ever done, family of 4 for 5 days to the beach with no resupply, bringing firewood, water for showers, etc... it weighed 8300. Not kidding, on a scale. So that is some background.

The real upgrade you should look at, IMO (which you will need larger 17" wheels for):
get a late 5th gen 4 runner brake upgrade. I bought new calipers, and the EBC sport rotors and extra duty (the most aggressive pad for heavy vehicle, non race) pads for the 5th gen 4 runner. Bolted right up with trimming to the backing plate (or buy 4 runner backing plates). They have larger pistons in the calipers for more hydraulic force applied. This is a big difference but will make your brakes more soft, not only cause the larger diameter of the new caliper pistons relative to master piston size, but the EBC orange pads are a soft feeling pad as well, they bite really hard at the same time they don't feel very firm on the pedal. The TRUE best thing you can do to the brakes though, is get the dual diaphragm booster from a sequoia or tundra, and put that in. It will double the boost of the power boosted brakes compared to the crappy single of the taco. To do this, you need to get the master cylinder out of the same vehicle since the bolt pattern on the master and the booster are different. I picked up the pair at an auto recycling place. It will bolt in with mods to the pushrod and some adapters and brake line mods. There are threads on this. Getting it bled properly can be tough. When you get the tundra master, it has a larger piston. then it is assisted with a dual diaphragm booster. and pushes onto larger pistons in the calipers. Compared to stock, this will put your head passengers into the seat belt when good pads and rotors are used.

If you choose to not upgrade the wheels and therefore not get the 4runner brakes, I would still do the tundra master/booster swap. If you have a TRD offroad, I would still do the 4 runner brake upgrade, it will work with the electronic booster still. But if you are firm on staying with 16" wheels, that will be your Achilles heel. The early tundra brake upgrade that does fit in 16" wheels is nowhere NEAR as good as the 5th gen 4 runner upgrade that won't fit in the 16" wheel.

I have also gone above and beyond with the rear brakes, when people told me they couldn't be improved. Bull. I understand rears do less work than fronts, no question that upgrading something that only does 30% of the braking will not have as large of an effect as the fronts... but when you are heavier, and the weight is on the rear, I feel the rears should be upgraded too, especially when you have done front upgrades making the imbalance worse. I put larger wheel cylinders in the back, and experimented with a few different types of pads. My testing isn't complete yet, and I haven't fully documented it. But I can tell you that a wheel cylinder size increase in the back does help for a truck like ours with lots of rear weight. When I get the brakes up to temp (sometimes I drag the ebrake a bit for 1/2 mile in cold weather), I have absolutely no problem howling all 4 35x12.5 r17 mud tires on a hard stop, and it is very controllable, very low pedal pressure.


If you want to talk more details, PM and we can exchange phone numbers. That would take way less time than what I just put into writing this.
I'm won't debate but you seem to be justifying your brake upgrade based on howling tires.....there is a LOT more to braking than locking up brakes, specifically heat management which is still going to be an issue.

Why SO narrow?? 235 is so much narrower than a stock tire even, doesn't make sense to me with a heavy truck. You will need to inflate them way higher than you would otherwise want, to support the weight, but then it is not much air volume to compress and absorb bumps... Even if you are into the pizza cutters (which are arguably better on a stock weight truck) on a heavy truck wouldn't you rather not have to inflate so much and have some comfort come from the tires too?

E rated is a given with that much on the back end, unless you wanted to inflate them way up and don't deflate or go offroad much. I tried a 35x10.5 Kenda Klever R/T on my truck, Load range D, and had to inflate way more than I wanted to carry the load. When you air down some it gets really squishy and not well controlled. Moved to a true 35x12.5 E rated tire, and wow, what a better difference for me in control, air pressure needed in a given condition, and traction. Granted I have to clearance a little more, but that is with 35, not 33.

My suggestion is to go with a 285 tire, your mileage is already bad, not gonna change much and it will support your load way better without over board on the pounds per square inch of the tire to pavement (note: not the psi in the tire). But if you are going to the 17", then a 255 80r17 is a better choice than a 235... IMO


of course actual measurements vary by manufacturer
235's were standard on 3/4 & 1 ton trucks not to long ago and all overseas Landcruisers come with a sim size, 7.5R16 or 225's......those are heavy duty rigs with GVWR's that far exceed the GVWR of a Tacoma.

On a heavy rig I'd advocate for the 235's over anything else, already a lot of strain on the light duty Tacoma drivetrain with that much weight and you won't be wheeling hard with a 8,000 lb Tacoma, I'd keep the tires as narrow as possible to avoid anymore stress.
 

jsnow

Adventurer
There is definitely more to braking than locking up the tires, and you made an excellent point on heat management. The Powerbrake rotors are 13.78" with 48 vanes to help with cooling. They also have paint marks on the edges that will basically melt off at different temps so if the brakes are getting too hot you can change to a different brake pad compound. There is a lot of R&D that go into these systems, and a lot of it is over my head honestly. All I am saying is that if I need to make an emergency stop, or brake quite a bit coming down a pass I need to be able to depend on my brakes to work, and in my situation they certainly do.
 

nickw

Adventurer
There is definitely more to braking than locking up the tires, and you made an excellent point on heat management. The Powerbrake rotors are 13.78" with 48 vanes to help with cooling. They also have paint marks on the edges that will basically melt off at different temps so if the brakes are getting too hot you can change to a different brake pad compound. There is a lot of R&D that go into these systems, and a lot of it is over my head honestly. All I am saying is that if I need to make an emergency stop, or brake quite a bit coming down a pass I need to be able to depend on my brakes to work, and in my situation they certainly do.
It's certainly a good start vs just throwing on larger calipers and saying brakes are upgraded like many do....it's at least quantitative and modeled vs thrown together based on perceived benefit or "intuition".
 

paranoid56

Adventurer
as another 7k truck, went with lots of things and could still fade them bad. what fixed it for me was just to bite the bullet and pick up the wilwood kit. 6pot calipers, 2pc rotors and good pads and i havent had issues since. it says 17" wheel, but fit behind my method 16s
 

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