DYNAMAX Complaints

Got an engine warning light while traveling. Our RV only has 67,000 miles on it. Cummins local dealer reports it is a Selective Catalyst Reduction (SCR) unit problem and unit needs a $10,000 replacement. This SCR is supposed to last 500,000 miles. Cummins refuses to cover the cost for this SCR repair even though Cummins issued a 2022-2024 voluntary recall acknowledging the problem_Cummins CR 2113. We never received a recall notice. Failure to replace will progressively lead to ghost error codes and eventually having the unit go into limp mode before stopping unexpectedly. Many people with this problem report a similar refusal by Cummins and some have been left on the side of the road when the unit fails because it is a difficult problem to diagnose.

Attached are pics of my failed 7 pole connector. The part number is (Hopkins #XXX). I took the RV to 24/7 Motorcoach and Victoria, Parts Manager, [XXX] Ext #5) filed claim #XXX on XXX. The claim was "Under Review" for almost a month. Now shows Approved Processing. I have a trip planned for tomorrow with my enclosed car trailer and did not have time to wait for the part. I purchased the replacement part myself from NAPA Auto Parts (Part #755-2621) and installed it myself. The same failure occurred. One of the pins pulled out and the lights/turn signals/brake/hazard/running lights/brake controller did not function properly or at all. I took the RV back to 24/7 Motorcoach and they removed the entire old back part of the connector which was connected directly to the 7 wires with spades, heat shrink tubing and silicone. They replaced the part with a different part (Hopkins #48474) which does not require a wiring harness. My Dynamax DX3 32KD did not come with a wiring harness. The original part #XXXrequires a harness to be installed properly and Hopkins sells an optional harness (part #40985) which MUST BE USED with part #40950. That is why the pin kept pulling out and the other pins were disconnected from the connector. In addition, the 20amp fuse in the engine compartment that provides power to the connector was blown. I have the blown fuse. I also have all of the part from the failed connector and all of the heat shrink and silicone pieces along with the failed connector. Clearly, Dynamax installed the connector incorrectly and this caused the failure. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

2026 Freightliner M2 106 Plus chassis (Dynamax Europa 31SS Class C motorhome), VIN [XXX], 6,803 miles, 0 engine hours. On June 9, 2026, an authorized Freightliner service center (Floyd's Truck Center, Belgrade, MT; service order XXX) inspected the vehicle and documented that the engine was secured to the chassis by only ONE mounting bolt — the remaining engine mount bolts were never installed at the factory. Under normal highway driving the engine torqued itself out of alignment. The dealer found the left-hand rear engine mount bracket required replacement and documented a leaking rear main seal and flywheel housing gasket, plus a crankcase breather oil leak dripping onto the driver-side leaf spring — repairs requiring removal of the transmission, flywheel, and flywheel housing. An engine retained by a single fastener is a serious safety defect: it can shift or detach during operation, risking sudden loss of power/control, driveline failure, or fire. Repairs are under Freightliner warranty claim XXX. This vehicle is occupied as a full-time residence and driven on public highways. The defect appears to have originated at chassis assembly and may affect other units from the same production run. No crash has occurred, but the failure mode presents an unreasonable risk of crash or injury. Repair documentation and photographs available on request. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Our rig started having problems leveling. The unit made loud popping noises that sounded like it was coming from behind and below the driver seat. Our local tech noticed that there were incomplete or cracked welds in the frame. We notified Forest River of the concerns and they insisted that the rig was safe. All other professional opinions obtained stated that it was not safe and needed to be addressed. This included a heavy duty vehicle weld shop. They would not even touch it. The rig was sent to Forest River in Elkhart, IN for warranty work. They stated that they were not going to do anything with the welds. We are very concerned that this could cause catastrophic failure and kill someone. Our rig will remain at Forest River as we are not willing to accept this response. I have included photos of the concerns. Their electrical system is not good either. The wires are pinched in the framing.

This unit is a cutaway Sprinter converted to a class C RV by Dynamax Corporation. I discovered a propane leak and in tracing it down, found that Dynamax had run their main propane delivery over a flexible hose. This hose was improperly protected from being damaged by poor installation process in that the hose was strapped to a cross member under the unit without consideration to protecting the sheath. I have just over 20K miles on this and the main sheath has a pinhole caused by it rubbing against a sharp edged metal cross-member. The cross-member is directly under the passenger compartment exposing us to fire and gas exposure. This danger could have easily been avoided by either putting a protective sheath between the hose an the cross-member, or plumbing the entire length with black pipe. I consider myself fortunate that this leak did not present itself while driving down the road. I have attached pictures of both the cross-member where the gas line is strapped down and the pinhole in the gas line (verified with a propane tester).

While driving the vehicle, the air horns detached and fell onto the roadway and became inoperable. The air horn trumpets are metal and weigh a pound or so each. This has happened 3 times and I have had the air horns break again. The last time one trumpet became lodged on the front sway bar and dangled beneath the vehicle. It almost hit the drive belts on the engine.

RAM recall #C4B, affecting ABS and Electronic Braking. Recall in effect, but no parts available for fix. This recall has been in effect for a few years. This vehicle is a 20000 lb motorhome, and my family's safety is being compromised by RAM dragging their feet and delaying the supply of replacement parts. I've contacted two RAM dealers and RAM Customer Service to no avail.

ABS light and warning bell on and sounding. Traction control light also on. Diagnostic shows error code c0020-01, ABS pump motor electrical failure. A canvass of every Dodge/Chrysler part supplier and all other possible parts suppliers including junk yards in the US and Canada revealed “no part (ABS Hydraulic Unit, 6834. 7099 AC) is available anywhere in the US or Canada. I was advised that it would be unsafe to drive the vehicle. I am stuck 2400 miles from my home with no solutions from anyone including Dynamax and Chrysler.

My RV has a TriMark door lock which apparently has a documented history of failure which makes it impossible to open the door from the inside or outside. This has happened to me. The entire lock needs to be replaced so that the door can operate.

Chassis mounted propane tank disconnect failure (loose nut hardware). Pictures available for inspection. Occurred approximately 02Oct2023. Potential for full propane tank disconnect from chassis. Pre-delivery inspection April 2023. No inspections afterwards. No warning. Found the tank in this condition when performing pre-trip inspection.