While pulling my 32 ft camper in the mountains, my 1997 Dodge Cummings diesel losing power and overheats. It will not go more than 30 MPH. What is wrong?

there almost certainly will be a freezeplug in that area , but first make completely sure the coolant isn't leaking higher up and looks like from bell housing , get the area steam cleaned and make sure it's not from the head gasket or another freeze plug , 30 minutes spent doing this could save you time and money dropping the gearbox etc , hope this helps

You might want to repost this in the camper section. I would say you would have to contact the company if they are still in business.

u may have a sensor or computer issue--it shud be scanned--the fuel injector pump is the heart of a diesel-probly needs a tune, rebuild or new one--pick up a haynes manual for maintenance details or go chilton online

WARNING: DISCONNECT NEGATIVE CABLE FROM BATTERY BEFORE REMOVING BATTERY OUTPUT WIRE (B+ WIRE) FROM GENERATOR. FAILURE TO DO SO CAN RESULT IN INJURY OR DAMAGE TO ELECTRICAL SYSTEM .

1. Disconnect negative battery cable at battery. Diesel Engines: Disconnect both negative battery cables at both batteries.
2. Remove generator drive belt.
3. 

1. Remove generator pivot and mounting bolts/nut. The diesel engine uses a bolt at top mounting and a bolt/nut at lower mounting. Position generator for access to wire connectors.

1. Remove nuts from harness holddown, battery terminal, ground terminal and 2 field terminals. Remove wire connectors. A typical generator wiring harness is shown in. Wiring harness routing as shown may be slightly different depending on vehicle model and/or engine.
2. Remove generator from vehicle.

INSTALLATION

1. Position generator to engine and install wiring to rear of generator. Tighten all wiring fasteners as follows:

• Battery terminal nut-8.5 N.m (75 in. lbs.)
• Ground terminal nut-8.5 N.m (75 in.lbs.)
• Harness holddown nut-8.5 N.m (75 in. lbs.)
• Field terminal nuts-2.8 N.m (25 in. lbs.)

1. Install generator mounting fasteners and tighten as follows:

• Generator mounting bolt-All gas powered engines-41 N.m (30 ft. lbs.)
• Generator pivot bolt/nut-All gas powered engines-41 N.m (30 ft. lbs.)
• Generator mounting bolt-Diesel powered engines-54 N.m (40 ft. lbs.)
• Generator pivot bolt/nut-Diesel powered engines-54 N.m (40 ft. lbs.)

CAUTION :

• Never force a belt over a pulley rim using a screwdriver. The synthetic fiber of the belt can be damaged.
• When installing a serpentine accessory drive belt, the belt MUST be routed correctly. The water pump will be rotating in the wrong direction if the belt is installed incorrectly, causing the engine to overheat.

1. Install generator drive belt.
2. Install negative battery cable(s) to battery(s).

diagram should be under hood,, on top of radiator cover

i have a 2001 dodge with a cummings engine i can be driving down the road an the tacometer will stop working an i lose some power as soon as the tac starts working the engine will pick back up

Take it into Cummings agent and get them to put it on the check out box (in a KW its in the dash ) but they will be able to fix your problem in about 10 minutes.

Have a goodday

The first thing to do is to start monitoring the coolant level.
This will rule out the possible of headgasket coolant passage pin hole leak.
Headgasket can go at 170,000 miles+ Less if your truck is doing a lot of hauling.
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Have you try Amsoil diesel treatment?
It work well for me.
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I will ran the tank below 1/4 and fill up on NON bio-diesel blend.
Use Chevon diesel until you get the problem figure out.
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Water can come in three way
air condensation in the morning
coolant
fuel.

new: www.rockauto.com
used: www.car-parts.com

I have the same thing but mine is between 45-50 mph. I read about this a while back in a magazine for people that pull campers, the problem exists in all vehicles although its not as noticeable in every thing you ride in. There is a certain "point" at which your speed and engine speed reach, that causes a phenomonon that causes a vibration. Engineers relate it to "harmonics" which is a similar issue but in the electronic field of study. There is nothing you can do for it, and it varies from unnoticeable in some vehicles to driving you insane in my 1989 Mazda B2200. I had an '89 Ford F-150 that did it at 35 mph and a 2001 Dodge Diesel that did it at 45 mph, but those were the only three vehicles I've ever driven and noticed it.