5.7L Tundra Booster/GM 1- Ton Master Cylinder

Is anyone running either of these kits? I know that they're marketed towards people who've SAS'd, but they should also improve braking quality with the OEM 2nd gen discs and drums, right?

https://trailtoys.net/products/one-ton-master-cylinder-upgrade
https://www.rockhoundoffroad.com/product-page/1-ton-brake-master-to-booster-adapter-05-15-tacoma

 

This would be good for front and rear BBK kits.

 

So no advantage for just a front BBK? (I'm currently not even running a proper front BBK, but rather the GX calipers/pads, which frankly I haven't been all that impressed by after a few years of use.)

 

Did you do steel braided lines with the BBK? Those will improve your pedal feel more than anything.

 

@essjay how come not the tundra/Sequoia MC and booster upgrade?

https://www.tacomaworld.com/threads/my-2006-tacoma-brake-upgrade-edited.652471/

 

Unless I'm misremembering and the extended lines I installed aren't steel braided, yes.

I'll have to look into that. Certainly makes more sense, although I'd have to find somebody to weld up the correct length actuating rod.

 

gotta be careful when you start modifying systems, changing part of the system in one part might actually make the whole system worse if other parts arent correspondingly upgraded. Correct me if I'm wrong but most of the guys who SAS'd go BBK to deal with stopping 37"+ tires. So its more about pairing the upgraded master cylinder with the changes that a BBK brings to the rest of the braking system than anything to do with SAS.

i did the 13WH caliper upgrade instead of the 14 WA precisely because of concerns with change to piston size without upgrading the master cylinder. It's the same 45mm pistons (stock to 13WH), just allows for 338mm rotors instead of 319mm stock. From what i've read, guys that do the 14WA (48mm piston caliper) without upgrading the master cylinder experience more pedal travel & softness, which i would not be a fan of

tacomaworld @BLtheP has some really good info on this from his previous feedback he's given, i highly suggest reading this thread:

https://www.tacomaworld.com/threads/brake-upgrade-with-tundra-or-4runner-calipers-rotors.846883/

 

I actually did do 13WH. I'll give that thread a look, too.

 

I’ve forgotten some of what I learned before vacuum boosted non-Tacomas (aka 4Runners), but I do know that on Tacomas with the hydraulic booster and 45mm calipers, Toyota uses the exact same booster (and corresponding built in MC bore) on the 4Runners that have hydraulic boosters, despite their calipers being the larger 14WA with 48mm pistons. There have definitely been complaints about soft pedal - I think I’d probably like that because I find the stock Tacoma pedal with the hydraulic booster is a bit firm…but I don’t have wheels large enough to clear those brakes anyways so I’ve never been able to compare.

I know the Tacoma master cylinder bore on the vacuum booster setup is something like 23mm, but I forget what the 4Runner is. Pretty sure I tried to find it and couldn’t. It would be interesting to see what that is…I’m pretty certain it would need to be a larger bore because people complain about soft pedals on vacuum boosted Tacomas.

To chime in on what this thread is about, I don’t know the specs of that Tundra booster/1-ton master but I would suspect it will create a hard pedal. The booster might be stronge enough to do it, but typically components like that are better served mated to larger calipers (which is why they recommend it for SAS 1 ton style setups) to maintain a normal pedal feel/travel.

Can always try and see but I have a feeling the results on stock calipers will be too stiff. On the flip side, that setup might match the 48mm calipers decently, although still, 48mm calipers are relatively small compared to what a typical 1 ton truck uses…somewhere in the neighborhood of 55-60mm pistons and sometimes larger. Those need lots more fluid which is why they have the high volume large bore MC.

 

Within that thread, there's a link (maybe broken) to a vendor that sold a threaded extension for the rod so no welding required...just loctite.

The fittings from the tundra/Sequoia MC to the tacoma hardlines is the headscratcher. There was someone selling adapter lines but I think its NLA. And then some guys saying adapters weren't needed, etc..

 

Read through it on BART, and it sounded like some people used adapters with OEM (?) lines and others were getting custom-made 12" lines with the correct fittings at either end?

 

Correct.

 

the SoS 2001-2007 sequoia MC kit for 2nd gen tacoma rear brake conversions comes with some line extensions. I looked up some of the reservoir offerings on RockAuto for both and it appears they share the same M12 1.0 pitch on both primary and secondary outlets. So maybe just for extension purposes?

https://sosperformance.com/products/2009-2018-toyota-tacoma-master-cylinder-installation-kit

 

Yes you are correct that extensions are needed for thr tundra/Sequoia MC and booster swap. The extension lines are to connect where the tacoma hard lines end to the port on the Tun/Sequoia MC.

The extensions brake lines had the correct fitting to mate to the tacoma hard line and then on the other end, it had the correct fitting to screw into the MC. The confusion was between m10 and m12 (i think). Some reports said an M10/12 adapter wasn't necessary. Some people said it was.

Extension brakeline is definitely necessary.

The m10 to m12 adapter for that brake line is up for debate.

(I have photos of what im talking about and will upload shortly)

 

Actuating rod extension so no welding required. Loctite absolutely necessary.

 

Genuine Toyota sequoia MC (aisin). Mocked onto a factory Toyota tundra brake booster.

 

Stainless brakeline extension with Male/Female fittings. I believe the female fitting is M10 and the male end is M12.

 

The male/female fittings are definitely NOT the same size. Won't fit...





Hope these pictures help explain what's needed in the upgrade.

@essjay one caveat : the tundra/Sequoia components are physically larger. If you go this route, make sure you have space near the fuse box. Stuff like aftermarket fuse trays, S/C coolant swirl tank, catch cans, etc...eat up valuable real estate for the MC/booster.

 

Now that I think about it, some of the confusion made be due to which is MC being used. Maybe the port size on the MC is different between tundra and sequioa.

Here's my old FS thread on the SOS Perf kit. Some info in that thread sheds light on the various MCs, boosters and brakelines that we are discussing in this thread.

https://www.tacomaworld.com/threads/sold-sos-performance-master-cylinder-brake-upgrade.837044/