Hello all:
Not too long ago our fan clutch completely locked up and we needed a replacement. I am not entirely sure which clutch it had. We ended up putting on an AC Delco 15-4947 after reading on it here, there was a thread by Ken Burton where he did some research and found this seemed to be the best replacement regarding the specs of the fan and setup on the GMC, and also after reading success and failures of Hayden clutches here too.

I haven't put many miles on the coach with this new clutch but this past week we were in temps up to about 88 degrees out. (In MI, that's what we call HOT ). With the old clutch in this temp range , the needle would barely pass the quarter mark on the gauge, but it would also kick in quite often even on the highway and I'd hear the fan. Now, with the 15-4947 clutch, I noticed the gauge has gone as high as just between the quarter and half mark while on the highway, and I never hear the fan roar like the old one. But, when getting off the highway or slowing to 55 MPH or so, the needle settles back to the quarter mark.

I believe I've read that once it hits the half mark on the gauge, it's already overheating. Should I be concerned with the readings I'm getting?

Thanks in advance as always!
Chris