APU's Or Battery Packs

I have tried and tried to find out the answer to this question, but I am coming up empty. I would appreciate help if anyone can.

I have just finished reading the DOT regulation on the 400 lb increase weight allowance. And I understand it as much as any non-lawyer can.

What I am trying to find out however is something I read a few months back about the "battery pack" APU's.

The law is very clear about the APU and the weight allowance. But what I read was a statement from the DOT stating that the battery pack was not an actual APU. It still needed the truck engine to start and run to keep the battries charged. And therfore it was not a true APU and the trucks that had the battery packs did not qualify for the 400 lb weight increase.

The reason I ask this, I was just "forced" to take an over weight load and they quoted the DOT rule to allow the trip.

It was only 420 lbs over. I know I lost some with fuel consumption. But not enough by the time I got to a scale house. Luckly they were all closed.

But 100 lb is as good as 1000 when you cross that scale.

Please help if you can shed any light on this issue.

Keep it safe out here, the life you save might be your own. The Blue Angel.

DOT:

Department Of Transportation

A department of the federal executive branch responsible for the national highways and for railroad and airline safety. It also manages Amtrak, the national railroad system, and the Coast Guard.

State and Federal DOT Officers are responsible for commercial vehicle enforcement. "The truck police" you could call them.

APU:

Auxiliary Power Unit

On tractor trailers, and APU is a small diesel engine that powers a heat and air conditioning unit while charging the truck's main batteries at the same time. This allows the driver to remain comfortable in the cab and have access to electric power without running the main truck engine.

Having an APU helps save money in fuel costs and saves wear and tear on the main engine, though they tend to be expensive to install and maintain. Therefore only a very small percentage of the trucks on the road today come equipped with an APU.

APU's:

Auxiliary Power Unit

On tractor trailers, and APU is a small diesel engine that powers a heat and air conditioning unit while charging the truck's main batteries at the same time. This allows the driver to remain comfortable in the cab and have access to electric power without running the main truck engine.

Having an APU helps save money in fuel costs and saves wear and tear on the main engine, though they tend to be expensive to install and maintain. Therefore only a very small percentage of the trucks on the road today come equipped with an APU.

I've had both systems on trucks over the 4 years I've been driving. Only once has it come in play for me. I was stopped at an Alabama scale for an inspection with a gross of 80120lbs. That truck had the battery pack on board. I asked the officer about the weight and he said "You're good on weight. You're allowed 400 lbs for that unit." I've never asked again.

Wow what a can of worms you opened up, I hadn't heard of this so I searched it. 2005 Dot put in an exception to add 400 lbs , BUT it wasn't a mandate SO all the states are different and not required to follow .... Recently Map-21 came into effect and raised it to 550 lbs, but still not a Mandate,,,Google Dot 400 lb APU exception ,,, got to love the Govment

DOT:

Department Of Transportation

A department of the federal executive branch responsible for the national highways and for railroad and airline safety. It also manages Amtrak, the national railroad system, and the Coast Guard.

State and Federal DOT Officers are responsible for commercial vehicle enforcement. "The truck police" you could call them.

APU:

Auxiliary Power Unit

On tractor trailers, and APU is a small diesel engine that powers a heat and air conditioning unit while charging the truck's main batteries at the same time. This allows the driver to remain comfortable in the cab and have access to electric power without running the main truck engine.

Having an APU helps save money in fuel costs and saves wear and tear on the main engine, though they tend to be expensive to install and maintain. Therefore only a very small percentage of the trucks on the road today come equipped with an APU.