On the topic of gear drive fit and crank runout

[nw_guy4_fun]

First follow this link to see how to check runout and what the current allowable specification on sprocket and pinion side is.

http://www.box.net/shared/u3l51lli0o

I am really baffled and would be curious what others have observed or am I all wet here?

From 99-02 installing a gear drive was usually standard gears right out of the box.

All of the issues began with the 03 model year IMO. Before that the cranks ran much more true from the MOCO. I am sure just by nature of the design the Timken contributed to that and the radial movement increased with the change to the Roller. Heck there has been at least 3 updates on that bearing since 03. So the crank was trussed better with the Timken and this put less emphasis and load on the camplate bushing.

Would be hard to prove but maybe not that hard, has the MOCO relaxed the tolerance allowable for runout? My 02 SM says .004 max IIRC and now the spec rises to .010. Maybe the SM meant on a truing stand. Got to wonder why and how the spec grew and if it really did or I am mixing up testing methods. What about all these bearing updates. A roller is crap at handling thrust load given but did the MOCO raise the C- number to add clearance for these new relaxed tolerances?

Can't you visualize an across department engineering and marketing effort in the interest of eliminating aftermarket competition.
Well Willy G has a little of Bill Gates in him from my viewpoint and I am sure is capable of that.

[bwana01]

Just sloppiness!! Willie is not that smart!!!

[HDMD88]

I have to agree with your findings although I have han several 02 and earlier engines that I had to use .0005 under sized rear cam gears. Only twice did I have to use oversized pinion gears in the earlier engines. Now days when I order a gear drive I tell them to take out the pinion and rear cam gears and replace them with over size gears....I haven't used a stock (out of box) pinion gear in years.

[nw_guy4_fun]

Originally Posted by HDMD88

I have to agree with your findings although I have han several 02 and earlier engines that I had to use .0005 under sized rear cam gears. Only twice did I have to use oversized pinion gears in the earlier engines. Now days when I order a gear drive I tell them to take out the pinion and rear cam gears and replace them with over size gears....I haven't used a stock (out of box) pinion gear in years.

Doc
I am in total agreement I was really only thinking in terms of what was happening with the front gears related to crank runout. This whole design would have been so much easier with 3 front gears. Now we get into the packaging and style area though, sure don't want to mess there