So the truck had a stumble, hesitation . Changed lift pump, had about 250,000 km on it and the crank shaft sensor changed. Ran like new. Then needed to crank longer before starting. Now starter turning very slow. 150 amp booster on and will not keep speed up. No start now. Could the starter be going? thanks in advance

 

Start with simple things first like, get the batteries load tested, make sure ALL your connections are clean and the grounds are good.

 

If it still cranks slowly after that, then replace or have the starter overhauled. Had to start my 01 in -20°F one morning. The power went out so the block heater wasn't working. The engine cranked over slowly, but still started.

 

Thanks for the tips. So far I cleaned the battery connections and the crank starts out fast and in a couple seconds drops to a very low speed again. Checked batteries and one appears to be dangerous low on draw volts. Hooked up a large tractor battery and a 150 amp booster and same thing, slow crank speed. Swapping out the starter now. Hope this fixes it.

 

If the one bad batter is shorted internally, then nothing hooked up externally will help.

 

This!!!!!!

 

Just remember in dual battery setups, it is always good practice to replace both of them at the same time when one goes out.

 

So I had one battery very low on amps and one was not holding charge. Replaced with 2 new batteries. Batteries were only 1 year old. Still didn't spin so changed starter. Works great!!! Opened up old starter and smelled burnt wires . Armature was worn and film of oil on inside. Blame the crankcase vent. Will reroute this tomorrow. Thanks for the help

 

If the starter you pulled out is the original, hang on to it. They are one of the best things that Dodge chose to use on these engines. Very well built and you can get several rebuilds out of them.

Heck, mine just got a new plunger and contacts earlier this year. Not bad for 14 years on the original.

 

This may be the original starter. I will have a fella look at it and see if this repairable. Thanks for all the help again

 

i have a brand new one in the garage just waiting for the original to go bad, i did install new contacts a couple of years ago and still cranks strong at almost 300,000 miles

 

Mine is still original with 330k on it.
if needed check here for rebuild parts from individual parts to complete kits as well as brand new denso starters
Larryb - Dodge Starter Parts - Dodge Cummins Diesel