Hey guys. I found out today that my alternator isn't working correctly because it was running below 13v today engine on and below 12 engine off after I put the new driving lights in (they were off). Basically, I went to Advance Auto to get new battery cables to try to do at least 2 out of the 3 wires as part of a "Big 3" Upgrade (4 gauge for Battery + to alternator and Battery - to frame: is that what it is called?) and I had them test the alternator. They see a ripple in the alternator and they said it is starting to wear out and that it can damage the battery if the alternator isn't replaced. They also said that if the battery is bad, it can damage the alternator. The battery, starter and charging system were ok, but it was the drain test where the printout said "SUSPECT". The guy also mentioned the "ripple" and how it shows the alternator's health. I am going to see if they have one in stock tomorrow (they are open on Easter), buy it and get it back to my apartment and see what I can do about putting it in. I'd rather replace it now than have it fail on the highway on Thursday on my 120 mile drive home.

I found this:
http://www.handymanlyness.com/archiv...ce/99_gmc.html

Is there anything else I should know before I go tearing everything apart? Anyone who has done it before have any tips?


Also is there any way to do it without a breaker bar? All I have is a socket set with a 3/8" drive ratchet, an emergency kit with basic tools (but not a breaker bar that would fit) and a computer repair tool set (I am an IT Network Administration major student). Thanks.

 

UPDATE: I replaced the alternator with a remanufactured alternator from Advance Auto Parts (129.99 + 25.00 core). They were open today on Easter Sunday and they had the part in stock (probably because this town is full of these trucks and they sell like hotcakes!). I bought a breaker bar anyway just to have for my tool kit and I managed to get the serpentine belt off without a hitch (I just hope I put it back on right!). I was surprised how easy the belt tensioner rotated. It was smooth as silk. I tried to upgrade the alternator to battery wire with 4 gauge wire and there was not enough space between the battery wire and the battery to make it fit, so I am saving that mod for a later date when I have the battery connectors replaced. I used a wire battery brush and made sure all the connections were clean. Getting the alternator off the engine was difficult because even with the bolts off, I had to use the breaker bar and a flathead screwdriver to pry it off the engine. The only real trouble I had was getting the anti-corrosion boot back onto the alternator terminal. It is stuck. I may just get some liquid electrical tape later and give the connector a shot of it. This was the first MAJOR part I have ever replaced and it worked out very well. Only took me 2 hours and I took my time. It is holding 14v even with the rear defroster, heated seats, high beams, radio, radar detector, GPS, interior LED lights, and A/C on high. Before, the voltmeter was dipping and the headlights would dim just from the rear defroster. also had it retested by the same Advance Auto Parts store less than 24hours after the first test. The guy even had me turn on everything this time (before it was just the high beams and the A/C on high) and the numbers were alot better. Now the voltmeter barely moves below 14. I heard that getting a shop to do it was going to cost $300-600, so I saved alot of $$! Even my mother was surprised and she originally told me that I was not going to do it myself, but to bring the truck home (120 miles) and have a shop that she is going to choose do it. I told her that I was not going to allow a mechanic to touch my truck without my permission and that she didn't have a say in the matter. She eventually gave up and let me get the reman. part and put it in. I was originally going to get an alternator from a salvage yard to try to save even more $$ and she freaked out. She was very glad to hear that it was working as well as it is and how much money I saved doing it myself!

 

Great job on the do-it-yourself fix. I remember replacing my first alternator or starter... cant remember which now, but the feeling was great. My wife doesn't understand how I enjoy buying used vehicles that need a little work and spending time lying underneath them. It is the satisfaction of doing it yourself that you have just enjoyed.

Congrats.
-Sean.

 

good job! would love to see some pics of those LED lights!

 

Thanks. The pics are already on the album on my garage. I will post up some updated pics soon. Those pics are a few months old when I was going to college at SUNYIT. I got some new gear since then over the holidays.

P.S.: You go to Morrisville? I got alot of friends who go there. I even visited there for the Open House on October 17th, 2009. I was going to transfer there, but it felt it was too far from home to be driving it every other weekend (like I was from SUNYIT to get away from all the B.S. in the dorms). I transfered to Cobleskill after only 1 semester at SUNYIT and I am now an off campus commuter. I have an apartment 5 min away from the commuter lot here.

 

Thanks. Because of the high cost of repairs, I am trying to do as much as I can myself. The repairs I can't do I shop around first. Like in town here I went to one shop and they wanted $1200 just to do both wheel bearings (the guy dropped it to $925, but there was no way I was going to pay that). I went on the college's website and there was another business about 25 min away and they did it for $325 (with tire rotation and installing a fuel filter I bought!). My specialty is computers, but I am pretty good with anything mechanical if I try at it. I also learned that sites like repairpal.com are not realistic and that to double their estimate to get what most shops will try to charge. My mother hates me working on my own car ever since I tried to replace the power window motor and I had to give up because I didn't want to cause damage and I didn't have good instructions. At least I knew where to stop and have a mechanic we know replace it. Only took 2 hours and he didn't charge alot.

 

yeah 1200 for wheel bearings is a complete ripoff! I brought the 50 dollar part to a buddy of mine's shop and he charged me an hour to fix it so all in all it cost me $110 bucks for one wheel bearing. It makes me sick when people try to rip people off.