Engine/Transmission (1998.5 - 2002) A good reason NOT to buy the Jacobs exhaust brake

[jlccc]

Just installed my Jacobs brake and I'm feeling proud of myself. Latest outing with the travel trailer and the exhaust brake was awesome.



But, pulling big hills tells me that I need a larger turbine housing to control the EGTs. I'm thinking a 16cm non-wastegated for about $150 should do the trick. No problem you say? WRONG!



Unlike the Pac-Brake and most other turbo-mounted exhaust brakes, the Jacob's butterfly elbow has a cast flange that bolts directly to the back of the turbine housing. This means that the only housing I can upgrade to is a 14cm WASTE-GATED housing at about $425. The Pac-Brake uses an adapter plate with a v-ring connector rather than the cast flange that the Jacobs uses. Hence, the aforementioned restriction to using the 14cm housing. DOH!

 

[MikeR]

Kinda sort sorta. If you had bought the Jacobs brake for the 98. 5 year truck it would have the same two-piece elbow with V clamp like the Pac brake uses. Cummins used the two-piece elbow from 94-98 then changed to a one piece elbow in 99 and changed the cast flange on the exhaust brake along with it.



I used to have the 98 Jacobs brake and noticed the flange, and I liked that setup better. I know the info is a little late, but it can be done.



-Mike

 

[Whitmore]

jlccc

I have a buddy with a 2001 eth dee that wants a Jacobs, if the price is right I will buy it from you... ... ... ..... PM or e-mail me if interested... ... ... ... Kevin

 

[Boost]

I bought the 16cm housing 2 weeks ago and found out the same thing. It is still sitting in the garage. I have to send it back or sell it to someone who can use it. Bummer!!



Rob

 

[jlccc]

Originally posted by MikeR

Kinda sort sorta. If you had bought the Jacobs brake for the 98. 5 year truck it would have the same two-piece elbow with V clamp like the Pac brake uses. Cummins used the two-piece elbow from 94-98 then changed to a one piece elbow in 99 and changed the cast flange on the exhaust brake along with it.



I used to have the 98 Jacobs brake and noticed the flange, and I liked that setup better. I know the info is a little late, but it can be done.



-Mike

While I'm certain you are correct, I bet the earlier model you mentioned was designed for 35# springs and not 60#, hence it would have been less effective than the unit I have now.

 

[MikeR]

No it was not made for the 35# spring trucks. The 35# spring trucks were 12v, that's a different brake. The brake I had was made for the 98. 5 24v truck with 60# springs, and the instructions said it it can be used in 99 and later trucks as long as I bought the 2nd piece of the 2-piece elbow which was sold separately.

 

[jlccc]

Thanks for the followup.