Jim Dynomite

My Jake brake's hissing noise is louder in the engine compartment than the tailpipe.

My 99 is the opposite, it's louder at the tailpipe. But it has aftermarket exhaust and louder engine noise. So that might be why I can't hear it at the Jake.

My 06 is so quiet I can hear water flowing through the radiator .

Just curious if anyone else thinks its louder under the hood than out the stock exhaust.

Hope I don't have a leak at the flange gasket. I shined a light down at the gasket at night to see if I could see any smoke coming out, but the darn thing doesn't even smoke out the tailpipe. What's wrong with this thing?



TIA................Jim

carharttfarmer

just got my jake on and it hisses alot to but i can run my hand all the way around the turbo clamp and no air is coming out but if you get under the hissing sound is coming from the exahust pipe and it stops at the cat

97Dually

Nope--your not nutts!

Mine has never been very loud, nor extremely effective at breaking a 5000lb boat. I'm not so sure I would reccommend the one from Cummins. I have heard the one from BD works fantastic. Honestly, it slows the truck better by itself. Once the boat goes on there, not alot of help.... Kind of alot of money to find that out.....oh well...

Tom

Smokeman

Jim Dynomite I can tell you the "hiss" out the tailpipe is significantly louder after I removed the factory muffler and CAT and replaced with the 51" Nelson.

97 Dually there must be something wrong with your setup because I find my EB will hold the truck, trailer and quads (22,000 lbs) on a 6% grade no problem. In fact it will cycle on and off with the cruise control on that kind of grade.

robert chilton

Yep it is loader under the hood. They also dont work well under 2400 RPMs. Once below 2000 RPM you might as well grab another gear. My Jacobs/Mopar unit does do a decent job at a 23k GCVW but you really need to keep the RPMs up. I think that it would be worthless on an auto.

LVTony

Nah, it works great on an '06 auto.

Towing a 12K trailer, it holds just fine as it cycles on and off going down 6% grades. I have had it hold at 25 MPH down a 4% grade (stupid national park speed limit for a 4% grade ). I had to shift to second, but it held (and yes, the TC will lock up in second).

Tony

97Dually

Tony-

I agree that at 25mph I can see the brake doing something for me, you know--when in 2nd L/U auto. But, do you see much breaking at any speeds the auto is in 3rd L/U? Any speed more than 45mph, doesn't really slow me down... I see soooo little, I easy pick up speed with the boat doing a 6% decent.


Maybe the trick is staying in that 2ND gear L/U. I was afraid that I would turn too many RPM's. But the truth is, it don't do squat in 3rd L/U.

Tom

Smokeman

Thats what we are trying to tell you Tom, there is something not right with your setup? It should perform better than that for you. Is it the Jacobs, BD, or Pacbrake?

rustyshakelford

what the general feeling for a pacbrake for an 06 auto instead of the mopar jake? from all ive read the pacbrake unit provides more braking at lower rpms then the jake...thanks

brett

Frahm Dodge

The hissing is normal. I have not tried the other brakes, but the Jake will not engage under 25 or mph. It does work well for me towing about 7500 lbs. down a windy mountain road, but I do agree that it does almost nothing when in 4th gear.

LVTony

Tom,

The Jake Brake works pretty good towing down hill at grade, and that's in OD. I rarely use OD lockout (I always use T/H, even around town not towing). The cruise control will let it get about 5 MPH faster before cutting in the Jake Brake, so if you use cruise control, set the speed a few MPH lower than what you want to drive at while going downhill. After it starts to use the Jake, it will cycle on and off as it slows it back down to just under cruise set speed.

Anywho, there must be something wrong with your brake.


Brett,

From what I've seen/read, the Pacbrake probably does work a little better than the Jake, but I wouldn't hesitate to get another Jake. The nice thing about Pacbrake is you can use the air tank to run other things too. It would make it a lot easier to install air horns...

Tony

97Dually

Thanks Tony. I appreciate your input. I'll have mine checked out.

Have you noticed that the Tow/Haul mode "seems" to operate identically either on or off when the Jake switch is thrown on? I have a feeling that just throwing the Jake switch on puts the tranny in the exact same mode as the Tow/Haul mode...???

mj007

Yeah, I got a Jake from the dealer when the truck was new and didn't really notice 'THE HISS' until I took the cat off. You can really hear it when you stop in traffic next to another vehicle that's on the right and you've got a window down. I get some P*****O** looks from the blue-hairs in the Buicks!

carharttfarmer

the hissing on mine sounds like when you fill a portable air tank and is more noticable when thers something beside you but do get a sweet jake brake rumble from the motor

LVTony

Tom,

I haven't tried non-tow/haul mode with the Jake on and off. I'll have to play around. I suspect it's not quite the same. The shift points and down-shifting are probably the same, but I have to wonder if the higher fluid pressure is there too.


mj007,

A friend told me I had an exhaust leak. I looked at him and asked, "what exhaust leak" as I turned off the jake brake. The look on his face was pretty funny. I waited a few seconds and turned it back on. I got a pretty good double-take out of him.

Tony