2006 Hydroboost question.

[Ryan Buck]

The seam between my Hydroboost unit and the master cylinder on my '06 Denali has been leaking for a while and is getting worse. I have also noticed a small leak at the rod going into the rear end of the booster. Rather than just do the seals I think it makes more sense to replace the whole unit.

I watched a video to see how tough a job it might be and in the video the guy mentioned using the "improved booster" and that GM was using this new booster when replacing old ones. The newer booster is supposed to give better pedal feel. I can't find any info on this. The pictures looked like it was the newer '07 and up booster.

Does anybody have info on this? I am not going to try this change until I can find out that there actually is an improvement from someone that has done this. I'll just use the proper replacement one.

If you replace it by one from the factory. If you buy one from a Parts house good luck getting one that isn’t gonna week. I don’t know about every for one of them is good LOL

 

[adriver]

To be fair, snow drifter asked about installing, not replacing.

Yes, but I was responding to sunlitcomet, and not sure if I missed snowdrifter or not. I figured not only does it cover that too, but it gives OP some directed threads if they want to go searching for the "upgraded hydroboost" they heard mentioned.

 

[Musicars]

I had to have it done last summer on my 2006 xl Denali. It was not an easy job. A lot of labor involved. I’m assuming my replacement part was just the regular recommended OEM replacement. Couldn’t say which one it was for sure. But mine was leaking in the exact same place. Although my labor was more because we also replaced the part that it’s attached to it, which I think is the power steering pump, although I’m not positive on that either. We weren’t sure which side the leak was coming from so we replaced both and called it a day so we wouldn’t have to tear it apart again. Lol.

I'm gong to try to replace it myself. I had the same concern regarding not sure which component is leaking. It is all wet but nothing seems to be overly low on fluid. The seam is between the master cylinder and the hydraulic booster unit. So I would assume that is what was replaced on yours. Supposedly, if the brake lines are clean and not all rusty, it is possible to push the master cylinder out of the way and replace the booster. The leaking fluid on mine smells and feels like power steering fluid so I am going to try the booster replacement alone. No way I want to mess with brake lines and bleeding the brake system on this.

I have not heard any feedback about an updated booster so I plan on just using a stock replacement. Rebuilts seem to be running about $200. Occasionally a new one pops up for sale on ebay for a similar price. I just want to make sure I don't get someone's defective return if I buy a new one that is not from a dealer.

 

[adventurenali92]

I'm gong to try to replace it myself. I had the same concern regarding not sure which component is leaking. It is all wet but nothing seems to be overly low on fluid. The seam is between the master cylinder and the hydraulic booster unit. So I would assume that is what was replaced on yours. Supposedly, if the brake lines are clean and not all rusty, it is possible to push the master cylinder out of the way and replace the booster. The leaking fluid on mine smells and feels like power steering fluid so I am going to try the booster replacement alone. No way I want to mess with brake lines and bleeding the brake system on this.

I have not heard any feedback about an updated booster so I plan on just using a stock replacement. Rebuilts seem to be running about $200. Occasionally a new one pops up for sale on ebay for a similar price. I just want to make sure I don't get someone's defective return if I buy a new one that is not from a dealer.

Yes my bad it is the master cylinder behind the hydroboost unit. That’s a good deal on a hydro boost. I bought new and it was way more expensive.......

 

[SnowDrifter]

To be fair, snow drifter asked about installing, not replacing.

Poor phrasing on my part. Replacing a hydrobooster doesn't seem all that complicated. Have it on mine, at a glance, nothing seems particularly difficult on it. Hence my inquiry about one of the comments in this thread about why it's so difficult

 

[bottomline2000]

I'm gong to try to replace it myself. I had the same concern regarding not sure which component is leaking. It is all wet but nothing seems to be overly low on fluid. The seam is between the master cylinder and the hydraulic booster unit. So I would assume that is what was replaced on yours. Supposedly, if the brake lines are clean and not all rusty, it is possible to push the master cylinder out of the way and replace the booster. The leaking fluid on mine smells and feels like power steering fluid so I am going to try the booster replacement alone. No way I want to mess with brake lines and bleeding the brake system on this.

I have not heard any feedback about an updated booster so I plan on just using a stock replacement. Rebuilts seem to be running about $200. Occasionally a new one pops up for sale on ebay for a similar price. I just want to make sure I don't get someone's defective return if I buy a new one that is not from a dealer.

There is a seal kit hat a guy sells on eBay. It can wear over time and cause the leak. There is one main seal and the figure 8 one, but they give u 2 differnet sized ones. I have changed it by just pulling the front of the hydroboost off. No need to go under the dash and pull the whole system out..The kit includes the socket too do this.

You don't have to open up your brake system, just separate the MC from the hydroboost..make sure you pay attention to reassembly as there is a lever that controls piston movement and if you don't put it back together right you brake pedal will slam to the floor when u start the truck..ask me how I know and why I figured out a quick way to replace the seal the 2nd time..also make sure the seal faces the correct direction..

Also, your hydroboost works off of your power steering pump so the fluid you see is power steering fluid.

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/322790704249

Sent from my SAMSUNG-SM-T377A using Tapatalk

 

[malmed]

You don't have to open up your brake system, just separate the MC from the hydroboost..make sure you pay attention to reassembly as there is a lever that controls piston movement and if you don't put it back together right you brake pedal will slam to the floor when u start the truck..ask me how I know and why I figured out a quick way to replace the seal the 2nd time..also make sure the seal faces the correct direction..

Thank you, I will be tackling this soon, and this info helps a LOT!!

 

[malmed]

There is a seal kit hat a guy sells on eBay. It can wear over time and cause the leak. There is one main seal and the figure 8 one, but they give u 2 differnet sized ones. I have changed it by just pulling the front of the hydroboost off. No need to go under the dash and pull the whole system out..The kit includes the socket too do this.

You don't have to open up your brake system, just separate the MC from the hydroboost..make sure you pay attention to reassembly as there is a lever that controls piston movement and if you don't put it back together right you brake pedal will slam to the floor when u start the truck..ask me how I know and why I figured out a quick way to replace the seal the 2nd time..also make sure the seal faces the correct direction..

Thank you so much bottomline2000 !! You saved me a bunch of needless work...

I too just pulled the front half off the hydroboost, and replaced the bad seal and the figure 8 seal. Had to buy a set of the E type sockets, but it sure was worth it.

When reassembling it, I pushed the brake pedal in some, to make getting the 'lever' you mentioned, back on easier.... and the main rod to the brake pedal I pushed until it extended out of the hyrdroboost and held it with a small vice grip... got the lever on while sliding in the big cylinder carefully, slide it in til I could get the top E-bolt in a few threads, then wiggled and tightened the E-bolts til it was in place.

It was so easy I was scared I had it wrong... but it is perfect.

Thanks!!