Re: Pioneer Harmonic Balancers
I know this thread is a couple of weeks old now, but I've just been looking myself and the Pioneer application chart which is down-loadable
http://www.pioneerautoind.com/ lists both as fitting the SyTy and Sonoma 4.3 V6 so I can see why there is confusion, the 2622 is only listed for the 93+ though. Also if you look through the various GMC platforms the 2621 is specified as fitting both balance shaft and non balance shaft engines whereas the 2622 is only referenced as fitting 'without balance shaft' engines that cover our years (93+ which discounts Sy's and 92 Ty's). The DA-2621 is a 3 'spoke' design 6.13" od and the DA-2622 is 6.233" with what looks like a solid inner hub with 3 lots of 3 balancing holes drilled through it. It is also 3/8" or so wider overall, so would more than likely affect belt positioning/alignment. (without a scaled dimensional drawing it isn't clear exactly how the overall dimensional width difference would affect the belt pulley placement). The designs are very different in appearance and the 2622 is 0.6lbs heavier. Having not had my crank pulley off, I cant say for sure which is correct, but suspect that if all SyTy's use the same balancer, the 2621 as most have stated IS probably correct, as the 2622 is as I mentioned above only referenced against 93+ vehicles. Now whether the 2622 'would fit', I don't know. Maybe the simple check is the overall ring diameter and what 'Hood' says is correct.
As an aside anyone have any thoughts on ATP or DAYCO balancers sold through Rockauto? Good, bad or ugly?
