[Gkpaddock]

Does Newell use an Exhaust brake or a Jacob’s brake?

[Richard]

Jacobs

[Gkpaddock]

Thank you Richard.

George

[TJ Clark]

Is there a difference between the two?

I always thought Jacobs was just a brand name, not a type.

[360]

I could be TOTALLY wrong here but my understanding is that the terms engine or exhaust brake is synonymous with a Jabob's brake in that Jacob is just the name of the company that designed the technology. The other term we hear about which is entirely different is a transmission brake/retarder that is seen on some older Prevost coaches. Don't know if Newell ever employed a trans brake, but haven't heard anyone talking about it around here so i'm assuming they didn't, at least not on S60 coaches and newer.

[Little]

Jacobs type brakes open the exhaust valve on compression stroke, hence the name 'exhaust' brake. PacBrake and others close off the exhaust gas flow after the turbo. In most cases the PacBrake types are sort of useless. Volvo makes their own type of engine brake as well. The older Cats (1693 and 3400 series) used a retarder using engine oil as part of the bell housing. I have one if these in a 1973 Pete with the 1693. Engine oil heats up quickly in mountainous terrain. These are quiet but not as useful as the "Jacobs" style. Newer Cats use the 'Jacobs' type.