Chevy & GMC Vans

I did i seach on here on monday and didn't really see any info on ways to tell bad engine mounts this week i've noticed i can really feel engine vibrations to the point were at idle i can hear part of my dash vibrating. Mostly though i just feel the vibration through my feet and my passangers pointed it out yesterday.

on a probably unrelated subject the same time this problem crept up my voltage dropped to 12.5 max at 3000rpm and 11.7 at idle. I've been driving around like this all week i'm going to install a larger alt pulley back on today, try to get it to charge properly again but at this rate it's probably not going to start one day (i have a jumper pack in there all the time just in case so not TOOO worried)


HMB
Cobra

Engine mounts can definitely get bad enough to transfer engine vibration into the frame. The mounts on the "Smilie Van" were so bad the engine side of the mount was resting on the frame. Seriously annoying vibrations. New mounts stopped most of it. I think these 4.3 motors vibrate a bit anyway. If I have to do it again I think I'll Use OEM mounts. The aftermarket mounts aren't as good. Maybe the rubber part is a bit harder. There's still a bit of vibration that I can feel inside.
Your minimum voltage should be around 13.6. Sounds like an alternator is in your future.

i'm going through alot of alternators lately this is my third since NECO 08.... if i have to put another one in i'm ordering a 200 amp one from somewhere these delco and dns seem to be bad luck. I just looked at the mounts don't seem cracked a little soft maybe not as bad as you describe though. battery was at 10 volts i have charger hooked up to it now my battery light on the dash has not come on yet. could the problem be related to my battery...? (i doubt it) and i just got rid of my leaky extra battery i had too dammit.....

How are your wires to and from the Alt Pierre?

that is a good question if i could see them i'd tell ya i'll check out the ones i can find, the connect on the back of the alt seemed firm and all connections around battery were still corrosion free (surprisingly, winter will fix that tho).
the larger alt pulley helped this morning voltage stayed above 12.4 and was around 12.7 while cruising to work

Changing the size of the pulley is just a patch. You need to find out why the voltage dropped. If you have been going through alternators and are using the same battery, I'd be curious if the battery is bad. (Granted, there are also a lot of crap alternators being sold too.)

Pulley was intended to only be a patch (so i can keep going to work)
when we were trouble shooting the second alt(which was defective right off the bat) when the one i got at neco kicked the bucket i had two batteries both tested good. this is really making me wanna rewire the charging system right now.....

Just ddi a load test on my batt tested good noticed a nice sqeak, sounds like my alternator same sound i heard when my the first one died

drove home in 2nd gear keeping engine at 2700-3000 rpm and it charged fine as soon as the rpm dropped below 2500 would only put out enough power to keep it running and at idle it seem to be basically just running off the battery (i assume a voltage regulator problem?) i ordered a new alt 180 amp aftermarket should have it tuesday