Convert From Exhaust Retarder to Engine Brake

[Wego2gthr]

I have a 2015 coach with a 380hp ISL9. It currently has an exhaust retarder. Is it possible to upgrade it to an engine brake? If so, any cost estimates?

[Skip426]

Not sure if the cylinder head would have to be replaced, rocker shafts and valve cover and lots of wiring, exhaust work for sure .

It would be costly if possible , and I don't recall any posts on the subject , so maybe asking at a Cummins shop would be the best bet.

[tom chelbana]

Can be done but I would think 4 to 5K would be parts and labor. Join Cummins Power Club if you do and save 10% on parts and labor.
Newmar Man

[Fiesta48]

I just went thru several mountain passes this spring/summer. My same engine retarder brake worked great. Only occasionally had to use the service brakes. Changing is NOT necessary.

[dons2346]

Call Cummins,you will get one of two answers.


It can't be done or you will get a price that will convince you that your current retarder works just fine

[Wego2gthr]

Yours must work better than mine! In the past 3 years I’ve driven in every state west of the Mississippi as well as parts of BC and Alberta. I’m headed to Gaffbey, SC to get service work done and brakes adjusted/worked on. I manually downshift before going downhill and still have to use service brakes a lot. After driving Hwy 12 in Utah from Bryce Canyon to Torrey Utah you could smell my brakes. Buddy following in his rig said he thought he saw smoke. Something ain’t right!

[funjnt]

If brakes are smelling and smoking you are not in a low enough gear with retarder on. You must be in a low enough gear so you don't have to use your brakes for the most part. I have come down many mountains in my Peterbuilt with 80,000 Lbs. on and not had to touch brakes. Admitted I am a chicken about overheating brakes but I won't be the rig in the run out lane.

[hypoxia]

Originally Posted by Wego2gthr

Something ain’t right!

It sounds like it may not be working. Are you able to manually move the butterfly valve? Has it been lubricated?

You can open the engine access, drive it and have someone watch to see if the butterfly closes, that is the easiest way to see. Don't do it on dirt, it will be everywhere.

[Ray,IN]

I have an ISC engine with exhaust brake. It didn't seem to be providing enough retard, so I began looking for a problem; I FOUND IT! Exhaust manifold was broken completely in two right below the turbo @ $4 port. $3,100 later the exhaust brake works great again.

[DD788Snipe]

Originally Posted by hypoxia

It sounds like it may not be working. Are you able to manually move the butterfly valve? Has it been lubricated?

You can open the engine access, drive it and have someone watch to see if the butterfly closes, that is the easiest way to see. Don't do it on dirt, it will be everywhere.

I have and exhaust brake on my 400 ISL and it works great. In fact at low speeds I have to turn it off or it drives you crazy down shifting. Sounds to me like you have one of two problems. 1. The ECM or TCM is not programed correctly. 2. The butterfly isn't actuating. The 2nd could be for a number of reason. I agree with hypoxia. That's a good place to start.

[SlowJoe]

Another vote of it must not be working properly. I drove over the Big horns this summer and went down a 10 mile 10% grade. My exhaust brake did a great job of helping manage speed. I used the service brakes in the proper manner when needed and if my decent speed was lower I really would not have needed them much at all. As it was, the service brake usage was minimal.

[NevadaNick]

The ex brake on our 8.9 ISL in our Phaeton was marginal at best. We live in the west. I talked to a friend that works at Cummins and he said it could be converted to engine brake, but we have since sold it. I was also going to have it bumped from 380/1050 to 450/1250.

[1doodadd]

See the provided chart and look at page 3. I believe your in luck according to the chart and engine model numbers


https://parts.jacobsvehiclesystems.c...-Guide-Cum.pdf