Engine/Transmission (1998.5 - 2002) Ebrake and straight pipe

[jwinnie]

Installed my Jacobs Ebrake last night. I could not believe how loud it was at the tail pipe at idle. I have the stock exhaust pipe with just the muffler removed. Resonator is still in. The only thing I can compare it to is bleeding the air out of a large air compressor

Do I have to put the stock muff back on to quiet this thing down? or will a straight thru muffler make a difference? Any ideas?



Thanks,

John

 

[Mundgyver]

Welcome to the world of exhaust brakes The hiss is the exhaust making it's way around the outer edges of the brake.

 

[jmeehan]

Originally posted by jwinnie

I could not believe how loud it was at the tail pipe at idle.

How much time do you plan on spending at that location?

Mine sounds bad, but I'm IN the truck, and it's better then listening to everyone elses noise.

 

[SRadke]

I've got a straight thru muff and it's still plenty loud. These mufflers are designed to kill low frequency sound which this definitely is not. I don't let it bother me, that brake is the best investment I ever put in my truck.



-Scott

 

[CFAR]

The butterfly on the brake has a calibrated whole in it to allow some exhaust through. A hiss is normal. It will hiss with or without muffler.

 

[Mundgyver]

jwinnie,



ONe thing for sure, you will be saving your regular brakes. I have over 110,000 turns on my original factory brakes and still have right at 50% of the pads left. The cost of the exhaust brake will be paid back, hands down by not having to worry about doing brake jobs every 50 to 60,000.

 

[rbagley]

So how does the exhaust brake work? Do you get a reduction in performance because of the restriction in the exhaust? Can you use one with a automatic transmission?

 

[Mundgyver]

No reduction in performance. It blocks of the exhaust and you turn the wast exhaust energy into braking energy via cylinder compression. You can generate around 60 to 140 hp of back pressure/braking pressure, depending on RPM engagment. It is possible to lock the rear end up and have it hop and skip because of the braking forces. This can happen on an unloaded truck under extream conditions that border on abuse.



For use with an automatic, you will need to have the transmission modified for lock up as I understand it. Check with ATS or one of the other automatic tramission vendors. They can tell you what is involved.



No modification required for the 5 or 6 speed mush/slush box transmissions.

 

[CFAR]

Don't 12v's (5sp) need 60lb exhaust springs installed?

 

[SRadke]

Yes

 

[CFAR]

You guys need to quit goofing off at work!

 

[TPCDrafting]

I have the original muff but no kitten. It hisses more now than it did with the cat on. but as stated unless I'm loading horses, I'm in the truck and it doesn't bother me nearly as much as smelling hot brakes.