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I90Tom · 05-01-2015, 08:38 PM

I have a 2000 Newmar 38 foot Dutch Star diesel pusher motorhome on a Freightliner chassis powered by a Caterpillar 3126 engine with an Allison MD-3000MH six speed transmission. About 3 weeks ago, we left Death Valley National Park westbound on State Hwy 190. As I recall, the warning sign at Towne Pass said 9% GRADE NEXT 6 MILES. I had my exhaust brake switch on and the tranny did its best but as we kept accelerating, it upshifted itself to protect the over-revving engine. It was as terrifying as any ride at Disney World. I was able to stop at the first pull-off to cool the brakes and my mind. I couldn’t slow down enough to pull into the 2nd one and any later pull-offs were just blurs. When we finally leveled out, the car following us down overtook us honking and pointing to alert us. As I was pulling off the road, I saw smoke in the mirror and quickly got out. Fortunately, the motorhome wasn’t burning. But my Acme EZE Tow dolly was. It has surge disk brakes and oil filled hubs. It got so hot that either brake fluid or hub lube spewed out and ignited. I saw yellow flames and black smoke as I ran back there. Water quickly put out the fire, but the oil in the hubs got so hot that water continued to boil off the hubs as we sprinkled it for several minutes. I think the black gunk splattered onto the wheel my Prius was the caliper dust cover. (Kudos to Acme, that extra braking capacity probably saved our lives!)

It turns out I don’t have either an internal engine brake or an exhaust brake on this rig. Freightliner’s Customer Support Center confirmed that my unit was delivered from the factory with a Jacobs exhaust brake. I suspect an earlier owner removed it rather than repair it, there was only pipe from the turbocharger to the muffler. I am hoping to hear from an owner with a similar motorhome, for a photo of his/her exhaust brake placement. I am especially interested in tracing the electrical & air connection originally used. My Freightliner store found the part number for a $895.00 Jacobs brand exhaust brake package for the Cat 3126 that includes everything including wiring and a dashboard switch. That would likely work without re-inventing the wheel. But my web research suggests a Pacbrake PRXB exhaust brake would work better. About the same price. Other ideas?

(This is a long post, suggest you use Quick instead of Quote or delete my text before you hit reply)
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I90Tom Betty & Tom from Fairmont MN (Flatlanders)
2000 Dutch Star DP (FL w/ CAT) 113K miles, very few up in the mountains!!
EZ-Tow Dolly and 2006 Toyota Prius 306K miles on original engine/motors & batteries

Skip426 · 05-01-2015, 08:57 PM

A belated Welcome to iRV2 .
I have the same chassis/engine combination, a year older , with a Jacobs exhaust brake , in good working condition. If you go Jacobs and need any kind of help PM me for pictures or any info I can provide.

I'm happy with the braking power supplied by this unit , and installed many Pac Brakes on Dodge Cummins , before I retired , so any info required there , maybe I can help.

EDIT: Guess I should have added , I don't have any pictures of the exhaust brake at the moment , but the coach is in the yard and I can take some in the morning.

Dr4Film · 05-01-2015, 09:10 PM

I took my first Alaskan trip with the OEM PacBrake. When I got back I ordered the PacBrake PRXB and have made another trip to Alaska since then and absolutely love the additional horsebraking that the PRXB provides.

However, don't expect too much from the PRXB at 55 mph and above. it performs the best at 50 and below.

Dr4Film ----- Richard

osok · 05-02-2015, 03:38 AM

Tom,

Is this a great site or what. You post a request for help and in 19 minutes Skip426 answers. Not only did he answer but also says to PM him for more questions and will also go out and take pictures. It just amazes me the support we can receive on iRV2.

I want to also add a belated welcome to the forum. Sorry I can not help on exhaust brake.