What size heims or joints are you going with? 1.25 is a little small for tube links. My heims are 1.25.
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I feel like I’m going to need 1 tons after this duramax swap. I’m either going to destroy the 80 tcase or the axles...I guess time will tell what happens!
In the past I used an adapter from Sky off road to go to a one ton master cylinder.
You need a master cylinder bigger than the T100 1 1/16” bore to feed those big calipers. Go hydro boost with 1 1/4” or maybe 1 5/16” bore MC.
Quick op-ed on brakes...
So the stock cruiser brakes aren't great, but they are trying to stop a heavy vehicle with fairly small rotors. Bigger brakes stop better, but they require more fluid. More fluid means a softer pedal. Unless you use a bigger MC, but then you get lower pressure in the lines. So you aren't really stopping any better if you size it equivalently.
Nowadays, even modern gas engines typically either boost the brakes electrohydraulically (UZJ100, 4th gen 4runners) or they use hydroboost (GM half tons, etc). So we're asking a lot out of the stock brakes.
Given the difference in caliper size, I needed almost twice the amount of fluid displacement to actuate these monster 1 ton front and rear calipers. I tried 4 different GM master cylinder sizes. a 28.6/40mm step bore, a 1.125 straight bore, a 37mm straight bore, and eventually landed on a 1.25" straight bore (off a 95 K3500 or something). The pedal is a bit soft, but the additional pressure really helps the calipers clamp the rotors. The other benefit of having a slightly undersized master is that you may still have a chance of stopping the vehicle if the engine dies or the booster leaks or something. This has real value to me - I want to know that if the rig stalls or dies or someone is under it and the booster is leaking, that I can still just mash the pedal with my body weight and keep it from moving. And this size does.
I'm running a hydro booster with 1 1/8' MC, stock 80 calipers, abs deleted and the pedal travel is well under 2" for normal braking. I could drive any trail bare foot and run the brakes with my big toe all day long. Diesel powered pickups have used hydro boost for years now and even some gas powered passenger cars have used it. It's not as expensive as you might think when compared to new, authentic Toyota parts especially if you can acquire some good use parts. A family owned business in southern CA called VanCo can hydro boost any vehicle and they know their business. If nothing else, they would be a good source of info for you.Well crap... I’m really not wanting to go to hydro boost ($$) and good to know about bore sizes.
I’ll read a bit more and see if I can find some more first hand experiences, but I’m glad you posted up before I order parts.
What would you guess you have into it as a total?I'm running a hydro booster with 1 1/8' MC, stock 80 calipers, abs deleted and the pedal travel is well under 2" for normal braking. I could drive any trail bare foot and run the brakes with my big toe all day long. Diesel powered pickups have used hydro boost for years now and even some gas powered passenger cars have used it. It's not as expensive as you might think when compared to new, authentic Toyota parts especially if you can acquire some good use parts. A family owned business in southern CA called VanCo can hydro boost any vehicle and they know their business. If nothing else, they would be a good source of info for you.
You'll be running huge tires and huge brakes, there is no point in toying around with the booster and MC.