10er

My son has a long commute (35 miles) before the sun comes up. Driving to work Thursday morning, he had an ABS light come on but didn't notice any other anomilies. He made it home that day, but almost didn't make it to work the next morning. When he tried returning home that afternoon, he only went a short way with the engine faltering, so he returned to the parking lot and got a ride home.

The ABS light didn't cause too much concern in the beginning, but could it have been a signal that the alternator was failing? Also, if the battery is totally recharged, could the truck be driven 60 miles home for testing and repair? I'm going to try getting it back with a full charge before having to get it towed. It's unfortunate that these sidewinder batteries can't be swapped out for a conventional post battery.

Should we just get a new alternator and hope for the best? And what alternator would you suggest? I'm looking at Duralast and Ultima. Any other recommendations?

oldchevy

Before replacing the battery or alternator, you should have them checked first. A fully charged battery should be good for 60 miles with a good alternator. If the alternator is bad then you could still be good but do not use any accessories. No lights, no A/C, nothing electrical. Also do not stop the engine as it may not restart. They also make adapters to use top post batteries in place of a sidewinder. I think the ABS light is an unrelated issue.

10er

I had the battery and alternator tested, and the alt is toast. I'm picking up a new one Tues to swap in. Decided to let the truck sit until then, rather than drive it home in our Horrendous stop and go rush hour traffic I would have hit. I would have certainly run out of juice before getting home. Thanks for your help!

10er

Just for entertainment, here's what finally happened:

I went up 2 days later and decided to drive the truck home rather than run the risk of not having a tool or something else swapping out the alternator. Since I'd be traveling mid-day instead of rush hour, I felt I had a much better chance getting home; if it ran out of juice, I could always pull to the shoulder and wait for a tow truck. Just to drop the load on the system, I pulled the fuse for the DRLs and turned off the radio. Did I mention that my son works at a lumber mill up the California coast? Rather far away from civilization.

The voltmeter showed a good 12v when I cranked her up, so off I went. Things went really well for the first 15 miles or so, and the voltmeter stayed right around 12v. This was no stopping highway driving at around 55 mph. Getting into town, I decided to speed up to freeway speed and eased up to 65. Things still went well for the next 20 miles. By then, the voltage had dropped to around 10.5v. It was running smoothly, so I thought I'd make it home easily. I only had about 10 miles to go. To my surprise, in the next 5 miles the voltage dropped from the 10.5v line to the red zone. I was now off the freeway and heading home on rural roads with only a few stop signs to contend with. By now, I was shifting into neutral and setting the parking brake to avoid keeping the brake lights lit. During these last few miles, the voltage went down quite quickly. By the time I hit my driveway (a half mile steep climb to my house), the gauge was down to the bottom. 9v. At this voltage, the engine started stuttering at low RPM, but it ran OK above 3K RPM. I shifted into 1st gear and powered up the hill to home. I made it! But just by a hair!

I came out a while later to read any codes thrown by the ECU, but only got a knock sensor code (I must have been dieseling up the hill!). I then tried to crank it over, just for a laugh, and it totally tanked. The next day I replaced the alternator, which was pretty straight forward, charged the battery with a charger, and everything is back to normal. I'm a happy camper!

SBchevyfan

Keep an eye on that battery. If it's an older battery it may not have liked being that fully discharged and may no longer hold a charge. The battery will need to be load tested instead of just looking at a dash gauge. Good Luck.

kevinkpk

The alternator incorporates the voltage regulator, probably what quit in it.