Brake system

[97 12valve]

Brand new here hoping to get some advice. I noticed my drivers side front fender liner was getting oily the other morning and traced it back to the brake booster. I would like to replace both the hydro unit and master cylinder at the same time is this advantageous or should I not really worry about the master as it has no signs of leaking. Truck has 380k on it as it sits. Also any tips on changing one or both items would be greatly appreciated thank you in advance!

[Mopar1973Man]

Could save a bunch of money and just get the seal kit for the booster. I think is 39 dollars for the hydro booster kit from Pirate Jacks.

 

I'm still using the OEM brake master at 422k miles. I flush the system every 30k miles. Still working fine.

[97 12valve]

Oh awesome I didn’t even know they made a seal kit I just figured it was a throwaway part honestly. Thank you very much! 

[Mopar1973Man]

Oh yeah flush the power steering system every 30k miles. 

 

Yes there is rebuild kits for just about everything on these truck nothing is throw away.

[CUMMINSDIESELPWR]

since you are gonna do major work on the brake system, might as well fluch it good too. i highly recommend getting this as it makes flushing/bleeding a breeze for one person... 

 

this specific one works for our trucks

https://www.motiveproducts.com/collections/domestic-bleeder-kits/products/chrysler-dodge-mopar-bleeder

[Mopar1973Man]

Simpler and cheap... Mayo jar and piece of tubing... Being using this for over 18 years never had any air issues. 

 

 

[97 12valve]

Awesome I will definitely be doing that when I do the booster! 

[dripley]

The beauty of doing just the hydro boost is you dont have to open the brake system.

[Mopar1973Man]

True. I just did one for a customer here locally and managed to squeeze out the hydro booster. Then split it open and replaced the seals. Then reinstalled. I will admit it was my first time of doing and there is a few then to be careful of... Like there is a small piece in the body which will most likely drop out when you split the body. Direction of that valve is important. Other than that the seal on the output shaft needs to be resealed most of the time. 

 

Total time for me was 3 hours. This is refilled and priming the system as well.

[97 12valve]

How can you tell which seals are junk just by sight or just replace everything once you get in there?

 

[IBMobile]

Replace everything when your in there or do the job again later. 

[Mopar1973Man]

There is one catch on some models of hydro booster you input rod has to be cut and re-welded back together to replace the input shaft seal. That was the one I didn't bother with. Only way you can tell is after you pull the entire unit out. 

[dripley]

Mine was staked like @Mopar1973Man mmentions. I did not do that seal and was very lucky it is not leaking. Yet.

[Mopar1973Man]

3 minutes ago, dripley said:

Mine was staked like @Mopar1973Man mmentions. I did not do that seal and was very lucky it is not leaking. Yet.

 

Thank you. Yup that was what I was talking about just couldn't get off my tip tongue... Did the job for a local carpet cleaner truck he's got a 2001 Dodge. 

Edited October 5, 2020 by Mopar1973Man

[97 12valve]

If the one I have is that way how would I know? The body won’t pull all the way apart when you split it? Or is there another way to tell

[dripley]

You can separate the body no problem. IIRC the shaft passes thru a whole in one half. There is a piece of stamped metal that connects the plunger inside the hydro boost to the pedal shaft. The connector is the problem. It is stamped on which makes it difficult to remove and reinstall. That is why I did not replace that seal.