After my purchase last year I have improved and fix a few problems on my tow truck and has performed quite well. Ever since I got it I noticed a slow cranking condition but it always started so it was ignored until this past week that I decided to fix the problem.

First I replaced the 2 batteries with 2 AutoZone 850A Gold's, then All battery cables in the truck were replaced with brand new Motor Craft replacements. The charging system was checked and the alternator was replaced with MOTORCRAFT Part # GL410 (F81Z10V346CARM).

The cranking is still slow so the next thing was to replace the starter. I read just about all the threads in this forum regarding replacement units and came up with the Denso units as a choice. I found a local supplier that has New Denso's in stock for a fair price ($145.00 + tax). It's not easy to get these replacements cuz all we have is Advance Auto, AutoZone and Pep Boys and the all carry the STD replacements. I still have some questions on the replacement that I will like to clear before I buy it.

1st. Mine is a 12 teeth/splines and the Denso is a 13 teeth. I believe that the larger diameter gear on the Denso unit allows for a direct replacement of my smaller 12 teeth without any flywheel problems, so correct me if I'm wrong. The size difference and location of the battery cable can be handled without any major issues.

Now, the supplier has 2 versions of the starter that look identical but one is made in China and the other is made in Japan. The price difference is $40.00 between both of them. My question is, are they equally the same? I'm inclined for the Japan made one so some recommendations here are needed.

I have a Pic below of my starter and the Denso unit with specifications. If anyone here has some info or opinions in this swap I will be grateful if shared.

Thanks, Andy