COMPLETED 5th Gen 4Runner BBK upgrade for 2nd Gen Tacomas

Sub for future project. Thanks OP and @tacomgee for the thread reference

 

Just did this yesterday. I need to bleed the brakes again because my pedal is super soft.

 

@buyoboyo did you end up getting the pedal sorted out? I feel like my pedal is slightly different but it may just be my head playing tricks on me. My pedal is firm but seems to engage lower on the pedal stroke. I was just curios if you noticed anything similar?

So far I have liked the new brakes, mainly because my last set of brakes were causing issues (vibration) but seems to work better. I have an armored (Front, rear bumpers, full sliders), bigger wheels and tires, and a canopy with bed platform. The truck is almost always loaded with stuff for recovery, jacking, and survival if I get stuck or broke. What are your thoughts now that you have had a chance to drive the new brakes?

 

My pedal is similar. There is a lot of stroke before it firms up. I plan on bleeding them again to see if it makes it better. I lost a lot of fluid (drained the reservoir to min) putting the passenger side caliper on.

 

I just completed this upgrade with stainless steel front lines and TRD Performance brake pads on my truck today with a lot of help from @EdinCincinnati!



We bled and flushed the brake lines until clear fluid with no bubbles was coming out at each corner. We also used the Toyota TechStream software to bleed the ABS module. And after my initial drive home (roads were wet, so no chance to do the break in procedure for the TRD pads yet) I’m not thrilled with the pedal feel. The pedal feels almost the same, if not worse than it did before with the same characteristics that @buyobuyo described. The pedal doesn’t seem to engage right away and when it does it feels somewhat firm but not nearly as firm as I had hoped. I know breaking in the pads will help a lot with the initial “bite” but I’m thinking there’s still air in the system somewhere and that I’ll need to try to bleed it again. I may order some speed bleeders and give it another shot.

 

So it is very much sounding that upgrading the master cylinder from 13/16" bore to a 1* bore is a necessary step for this upgrade.

 

@09TRDSport4x4 and @buyobuyo, have you adjusted your rear brakes as well? Mine were soft at first until I adjusted the rear brakes which firmed up the pedal feel. After doing the break in procedure and about 300 to 400 miles of regular driving my brakes have firmed up and feel a lot better now.

 

I have not adjusted the rear brakes @KCTaco77. I didn’t think I needed to since my parking brake only goes down about 7 clicks when I use it (I read if the parking brake only goes down 6-8 clicks that means the rear drums were properly adjusted). I’m going to attempt to bleed the brakes again tonight and don’t mind adjusting the rear drums while I’m under there, but I’ve never done it before. This is my first ever vehicle with drum brakes...

 

I agree with folks the pedals does feel different. From reading up upgrading to the 1" bore may actually make it worse. I can't recall who did it but they ended up swapping back. Also this would only work for sport models. Offroad with the electronic booster is a no go or too expensive to find say a 4runner version (possibly prep for rear discs)

Make sure you add the stainless lines if you did not. That will firm up the pedal. The other thing is adding ton's of steel and other things come into play. When I tested it with stock pads It was stopping quicker than stock. Since then I have added a ton of steel and I have had to adjust my braking due to various factors. I have some TRD pads on order from the recent 40% off so I will give that a shot and see how it goes. I also just went up to a 315/70/17 tires and soon have a swing out coming so I will be fully loaded down and heavy. I expect the braking will not be as good as the original post but I am curious to see how much.

Its also key to bleed the master and if you have an off road you need some help here. Overall Its been good for me, a few moments I feel its not been good but a lot has changed on the truck since then.

 

What’s the process for bleeding the master?

 

Since I have an auto transmission I don't have the lever parking brake so not sure how many clicks it should take for proper adjustment, but I've never had good luck with the rear brakes being adjusted correctly even though they are supposed to be self adjusting. I just jack up the truck till the rear wheels are off the ground and adjust them manually until the brakes start to drag when spinning the rear wheels.
Here is a how to video on how I manually adjust my rear brakes.
https://www.youtube.com/watch?v=iN6z0oIZLBk

 

Nope. Didn't adjust the drums.

 

Non-VSC bleeding
VSC bleeding

Drum adjusting procedure

 

We bled the brakes manually again today after work. Both rears were bubble free and a few straggling bubbles came out of the front two, but was quickly followed by a solid stream of clear fluid. The pedal feels less soft now than it did, but it still has a bit of a long feel to it (I have to push it down more than I’d like to get the brakes to engage). I don’t have to prime the brakes to get a firm feel, it’s a consistent feel at every push. And the longer press isn’t new to my truck, the factory brakes were the same way.

I’m going to try to find somewhere to break the TRD pads in tonight and then see how it feels. After the pads are broken in, I’ll probably drive it for a week or so then I want to try to bleed it again just to see if any more air comes out. Overall, I’m pleased with the upgrade but I won’t have a solid feel for any increase in stopping power until I get the pads broken in.

 

I did mine this weekend also and am battling the same thing. Feels like I have to push alot farther down on the pedal to get them to start to bite. Once they bite they do pretty good though. But if you are supposed to only get 6-8 clicks out of the e brake for it to work good mine rears need adjusted. My e brake goes to the floor and it still moves enough to catch the parking pall on my sloped driveway. I was going to use one of the tech's vacuum bleeder tomorrow night and flush out the super blue fluid I just put in it back in August but can't decide what fluid to go with to flush it with. Thinking I will try the Pentosin. Really hope I can get the pedal feel back as I love to feel the brakes bite high up on the pedal stroke.

 

Broke in the pads last night using the TRD Performance instructions (10 consecutive 60 to 5-10 mph hard stops without completely stopping until the brakes have time to cool). The rotors now have a nice bluish tint in the veins and a grayish film on the surface from the pads (exactly what the instructions said I should see). Drove the truck to work this morning and the pedal feels a bit firmer but still doesn’t engage very high. The instructions say I’ll need to complete another heat cycle before the pads reach optimum braking performance so I may take it out again later and do a few hard stops to heat it back up.

Overall, I am very happy with this upgrade. I think the pedal travel is always going to feel a bit long compared to other vehicles, but the stopping power has definitely improved. During the first several hard stops last night the brakes felt stronger than my OEM setup ever did and as the pads continue to break in the pedal should have even more of a “bite” to it. I’m gonna drive it for a week or so and try to find a wet or gravel road to kick the ABS on a few times before I bleed it one last time. I’m hoping if there’s any air left in the lines a few more hard stops and forcing the ABS to kick on will push the bubbles out towards the calipers and drums so that I can get it all out with the next bleed.

And in the meantime I might pickup stainless lines for the rear to install with my next regularly scheduled brake fluid flush. I’m definitely going to stay on top of keeping the fluid clean and clear.

 

Adjusted the drums last night per the FSM and bled the brakes using my PowerBleeder. I got a few micro bubbles out of both fronts and the rear passenger, but I'm not certain whether those were actual bubbles or something that formed in the drain tube as it filled with fluid. Either way the pedal feels a lot better. I'd dare say that it's back to how it was before at least. I didn't a couple of hard brakings to do a little pad bedding. The first one that I did felt pretty good. The next one that I did the pedal gradually sank to the floor the more I pushed on the pedal, which was a little disconcerting. The pedal was pretty squishy again after that but firmed back up after a bit. I didn't get a chance to do any more hard brakings cycles before I got home.

 

After breaking in the pads and driving on this setup for a few days now, I’m convinced there’s still air in the system. The new calipers, rotors and TRD pads definitely bite harder than my OEM setup ever did, but the pedal still feels too soft. I’m going to try to find time to adjust the rear drums and bleed the brakes again this weekend or early next week. The truck stops great right now but if I can firm the pedal up a bit, I’ll be extremely satisfied with this upgrade.

Also, I want to add for reference, that the 5th Gen 4Runner calipers fit great behind the OEM 30mm offset Sport wheels with 1” wheel spacers. This makes sense seeing as most 4Runner wheels have a 5-10mm offset but I just wanted to confirm for anyone else who uses stock wheels.

 

If you put in stainless braided lines to replace OEM rubber lines, need to do this on both front and rear, otherwise you will feel an inconsistent braking.

 

You know, I was thinking about that last night. I think I’m going to order rear lines and speed bleeders. Once they arrive I’ll adjust the rear drums, install the speed bleeders and rear stainless lines then bleed everything again. I’d like to think that doing all of that should firm the pedal up as much as possible.