Is there anyway to tell which alternator I have on my suburban? I went to Oreily's this past weekend and there are three different ones ranging from 110-140 amps. I was just going to get the 140 and then I got to wondering if the mounting holes will line up, if the plug is the same and if there is the potential to burn something up due to a higher amperage.

Also here is a brain buster......... a rebuilt unit is MORE expensive, does not have a lifetime warranty and has a higher core charge than the brand new ones! Same manufacturer...... So here comes the stupid question. Would there be any reason to buy a rebuilt unit rather than a new one?

Lastly, I didn't recognize the manufacturer. I believe it was Ultima. They come with a lifetime warranty but a lifetime warranty isn't going to help me when I am stranded on the side of the interstate 250 miles from my house. Anyone have any suggestions on what brand I should go with? Usually I like going with Delco but I am having a hard time finding an Auto part store that carry them.

 

They'll mount up. I'm running a NAPA 200Amp alternator on my truck, they all used the same alternator bracket from 99+, and I believe still do even on the NNBS.

Google results say do not buy an Ultima.

Bosch makes good alternators according to google, a quick search also brings up what auto parts store you can get them at.

 

Eh. The Ultima alternators are straight up junk. The Bosch alternators are so-so, have a higher than expected failure rate for Bosch parts. I would recommend replacing with a Delco #10464453 130A alternator. Keep in mind that when you get a new alternator that the belt needs to be changed to fit the amperage model. I think there's a few MM difference in belt lengths between a 105 and 130A alternator.

You can spring for a custom high output alternator but I wouldn't spend the extra money unless you needed it for some reason. The amperage output doesn't matter a bit, too much is NOT going to hurt anything. Too little will run the battery dead, though.

 

Thanks for the help guys. I will try to find the Delco that was suggested above.