Newmar Corporation (Newmar) is recalling certain model year 2004-2007 Essex motorhomes manufactured March 24, 2003, to March 7, 2007, and 2005-2007 London Aire motorhomes manufactured May 30, 2005, to October 23, 2006, and 2007-2008 Mountain Aire motorhomes...
Engine & cooling
Newmar Mountain Aire Engine problems by year
4 complaints filed with NHTSA about the Newmar Mountain Aire's engine & cooling. Stalling, loss of power, oil consumption, overheating, head gaskets, timing chains and engine failure.
Engine complaints by model year
Engine recalls
Latest Mountain Aire engine complaints
My motorhome is currently in a Freighliner shop to replace the 2nd defective DEF head in less than 19,000 miles since New. The defective DEF head causes a derate of power and total shut down and can leave you stranded on the highway or coming down a mountain pass with no power defeating the air compressor therefore no air brakes with a 45 foot, 58,000 GVW vehicle. In my case I was able to get off the highway before total shutdown only because I was aware of the built in shutdown design of the emissions system.
These vehicles, built on a Spartan K3 chassis and powered by a Cummins ISX-12 engine are experiencing very high failure rates in the DEF system control head. When the control head fails, it sends error codes that result in derating engine power dramatically and/or immediate engine shut-down. This creates a very dangerous situation for anyone driving a motorhome that experiences this problem. In extreme cases, it may stop the vehicle in traffic lanes. Spartan Chassis says replacement DEF control heads are in...
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extremely short supply and they will not provide one to a repair facility unless the affected vehicle has experienced a full derating; an initial warning message of a failing control head is deemed insufficient cause for them to provide a replacement part. Their official response is that "you must drive it until it fails before we will provide a replacement unit." This means drivers of these motorhomes will either be subject to sudden (and, potentially very dangerous) engine shut-down, or they must cease using their expensive motorhome until such time as Spartan Chassis feels they again have a sufficient stock of replacement units. Many motorhome owners use their vehicles full time; they are their home. The inability to safely use them places a huge burden on those owners. I believe NHTSA needs to issue a recall on affected vehicles and direct Spartan Chassis to implement a software emergency bypass of the engine derating caused by a faulty DEF control head. It is my understanding that this software bypass solution already exists and is currently implemented on emergency vehicles (fire trucks) produced by Spartan Chassis.
I purchased the unit with 25,000 miles. The def system failed enroute to the dealer I purchased it from and failed again after approximately 3,000 miles after repair. The entire def header was replaced. This is an extremely dangerous situation when the vehicle goes in to derate. My motorhome is 53,000 lbs and 45'. Add a tow vehicle and it is very dangerous when this happens. I was heading to las vegas nv from quartzite, az when this happend on a two lane highway. No place to pull over to even check anything. These def systems continue to be extremely problematic. There needs to be investigation in to how to keep these systems operating properly.
Vehicle running normally, accelerated to merge with traffic, engine began to miss then backfired. Miss continued and the vehicle wouldn't accelerate past 55 mph. Pulled to side of the road to check for any visual problems, none noted. Engine started normally and I finished the 30 mile drive home. Changed fuel filter, air filter and maf sensor. Engine started normally and I took it for a test drive. After 20 miles with no issues I attempted an acceleration and again it lost power, skipping/missing and...
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backfired. Pulled into a rest area and shut down for 20 minutes. On restart a check engine light illuminated. Obdii indicated that it was a p0342 crankshaft position indicator sensor issue. A mechanic indicated that gm did a recall on the 2001 8.1L vortec for this issue and that this should have extended to the workhorse w22 chassis with the same engine but didn't. I believe the recall should have extended to all 2001 8.1L engines. This is a serious safety hazard as it leads to an unsafe situation where the vehicle fails to accelerate or stalls when merging or passing. Additionally, the shutdown of the engine removes the power brakes and power steering creating an increased hazard to the occupants and those around the vehicle. *Tr
Source: U.S. National Highway Traffic Safety Administration (NHTSA) complaints and recalls, checked daily. Complaints are owners' own reports and are not verified. How we use the data