I have a dealer installed Jacobs Exhaust Brake. When activated, there is a loud hiss. Is this normal on the 04s? I rode in a friends 02 and his ebrake doesn't hiss at all. Mine has made this hissing sound since day one. I wasn't concerned until I rode in my friends truck and his was quiet. Any ideas?

 

sounds like some sort of pressure leak I don't sell jacobs nor have I ever had that expeirience I sell pac brake and bd never had such problem. take it back to dealer who installed or get a hold of Jacobs

 

ive never had one or rode in one but i "thought" the hissing sound was normal from reading other posts...

 

I own one. When you turn it on at idle, you will hear a hissing sound. It is normal.

 

Normal

 

If you don't hear a hiss at idle with a Jacobs, your ebrake is not working.

 

In this case, hissing is a good thing.

 

Thanks for the replies and I found the problem. The V-band between the turbo and ebrake elbow was loose. I tightened it up while it was warm and then again this morning. When I engaged the ebrake for warmup I heard the hissing from the tailpipe but at a much lower level then the hissing that used to come from under the hood. I don't know if the tech that installed it forgot to torque the vband or it worked itself loose. All is well again in my happy place

 

The v-band between the turbo and brake on the 3rd gens. should be checked periodically. I check mine at ea. oil change. They have a tendency to work loose. Have had to tighten mine twice so far.

 

My ebrake is screaming at me. Started on the trip in the mountains pulling the fiver. It sounds like a belt screaching. Dealer could not find anything "OF COURSE" because it was not hot and didn't have a fiver on behind and was not coming down a mountain. HMMMM, any one know where there is a mountain in Florida? It stops immediately when you release the brake. It also changes pitch in keeping with hitting of bumps. Nothing loose in the belt line. I guess I will have to live with it until I am in the mountains the next time and blow my belt. They can then come and pull me and the fiver in and replace the brake pump.

 

From what I understand, the reason the brakes were on hold for a while was because they could be mis-installed and cause a leak between the valve and the turbo outlet.

When I put mine in, it seemed like it would be easy to get the valve turned one way or the other, so that it wouldn't meet square with either the downpipe or the turbo...doesn't have a roll pin like the stock elbow it replaces. If you banged it around getting it in there, you could probably ding up the gasket.