Mopar Big Brake Upgrade Master Cylinder/Brake Booster

g00se04

New member
After swapping the Dynatrac HD 60 axles into my 09 JKU the brake pedal was a little softer than I expected after bleeding the brakes etc. Digging into the issue I found out that the
master cylinder that came on my jeep was a 1" bore and you can upgrade to a 11 or newer which had a 1 1/8" bore. I did the swap and the pedal
felt a little better but still not what I wanted or expected . I went online and order the Mopar Big Brake Upgrade Part Number P5160050 which has a bigger booster and a master cylinder with a 1.25" bore.

Got the kit and found out that its only designed for an automatic transmission so the reservoir doesn't have a outlet for the slave cylinder. Mopar does provide a part number for a slave cylinder that has no mounting hardware and is like $175 from the dealer.

So I had the bright idea to just plastic weld/glue an output on the reservoir for the slave cylinder and turn the new reservoir into the factory jk reservoir design. Well..... the plastic weld/glue failed and I wasted the reservoir. No big deal right? just order another reservoir and source a aftermarket slave reservoir.

It turns out all of the parts that compose the Mopar big brake kit are import parts only and are only available in the kit. I found this out after trying to get my dealership to order a replacement reservoir (68048758AA) which was rejected due to me not owning a Jeep that the part number belongs on even though I have a Mopar kit that it comes with. I tried to order that part number from a mopar online retailer and was also rejected as its a import part only. After much digging I was able to find some other poor soul that did the same thing and they found out that a US reservoir (5179927AA) . Dealer ordered this part for me and its the exact same thing that came with the kit. As for the slave cylinder I ordered a Wilwood WIL-260-11098 to resolve that issue.

Why am I posting this?

Well to rant about Mopar putting a after market kit together that is sold in the USA that you cant replace parts in due to the parts being import only.

But I am also posting this so if somebody makes the same mistake as me they will have that part number without going to the end of the internet to find it.

Can my Jeep stop now with the Mopar Big Brake Master Cylinder and Booster ? Yes. performance is better than factory and the pedal feeling has came back to normal.
 
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