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PERAs Core Corner
Understanding The Long And Short of Gen III Cranks
By Roy Berndt
It seems that the thirst for knowledge on the Gen III GM engine applications is growing almost as aggressively as the information for the 4.6L Fords. I addressed the subject of Gen III long and short crankshafts in a recent column (See September 2004 Engine Builder Core Corner). But based upon the number of responses from readers, it is apparent that there continues to be some confusion about when and where the long and short flange cranks apply. so let's look at an update and some additional information that should be helpful.
Let's tackle the long and short of it and see if I can't do it better this time around. It seems that many of you enjoy the explanations of how it all fits and comes together while you're sitting comfortably, reading the issue. But once you get out into the plant or shop, a chart is often the most convenient resource for reference, not having to read through the text in an article.
I'll be honest here: this is a simple task that I lost sight of not being "hands on" on a daily basis. I thank-you, the readers, for giving me that slap upside the head.
To make amends, I'm providing a chart of the differences between the crankshafts used in Gen III model years 2000 and 2001 since those are the transition years. As you'll remember from the September column, after 2001 the crank flanges are all short.
View chart showing various cranks used in Gen III GM engine during 2000-2001 model years.
The chart may be just like a wrench in the right place in the toolbox: knowing it's there, you'll be able to reach for it when you need it and put it away when you're done. Like all good tools, it can make your job easier but you have to use it.
A number of you have expressed that you are having difficulty obtaining the spacer and bolts from GM dealers even with the part numbers provided. Dealers either do not have them or say it will take too long to get them.
In my search for another source for spacers and bolts other than the dealer I contacted a number of core suppliers. My thought was that if they were saving and sorting them the parts might be available. While I was unsuccessful in that search, I did find a resource that has them available new: Engine Parts Plus in Melvindale, MI.
Sometimes the process of searching for information overshadows the need to present it in a worthwhile format. I thank you for the opportunity to give you what you need - and your suggestions on how to do it better.
For technical questions, contact the Production Engine Remanufacturers Association (PER) at: firstname.lastname@example.org