Hi Scotty, got a 2007 Toyota Highlander 3.3L v6 with 220k. The thing has went through probably 5 alternators in the last couple years. First the original went out back in 2019 i believe, so i replaced with a rebuilt advance auto one (bad idea) it ate three of those before i got a good one and it lasted quite some time. Then on a road trip from Ky to VA the AC got weak and warm and I assumed they refrigerant might be low but the blower motor seemed weak, so i made it to VA and the car failed to start next day- Dead alternator after i jumped it.... So i got a rebuilt from NAPA (which around here is known to have good electronics. That one lasted until last month and on our way to NC it did same thing, weak AC etc. Had to swap it out on the road this time... If done some research and cannot find much regarding why it eats alternators? All i found was the rebuilt are just crap now. Is there any reasons otherwise? I know i hate the manual adjuster bolt on the fan belt/alternator on this car, would that effect anything? Sometimes the belt squeals when u start up and I have to adjust the belt tighter.
Help please
Thanks
Waylon
How old is your coolant? My Mercedes was eating alternators and I noticed I had electrolysis in my coolant. I changed the coolant and I haven't gotten a battery/alternator light since.
@grizzzlygoat please copy paste your reply as ‘Your Answer’, below.
If it's too tight or too loose it can cause issues. I always hated this style belt tensioning system Toyota used. The other thing to check is to make sure you have good engine and ecm grounds. Bad grounds can wreak havoc on electrical parts.
Which one have you been getting, the 130 or the 100 amp alternators? Also found in the forums that is seems to happen a lot on the 1st gen V6 Highlanders.
I have been getting the 100 amps but with some reading I'm questioning just buying a brand new denso 130amp. Whats the best way to not over tighten the belt on those?
When I had my 1999 & 2002 4runner, I had 3 belts to eff with this eff'd up tensioning system. I cursed the living hell out Toyota. I used a belt tensioner tool that helped me out. Gates makes one, part # 91107, it's about $17+/- at the part stores. there are other ones out there but more expensive.
Thanks for the advice
A bad battery will eat alternators
True, Ive changed the battery between the first three and the second two. and it was check at the last one and was good.
What kind of alternators are you buying? If they are super cheap it is possible that they are giving you bad alternators.
I’ve tried advance auto and Napa both have been through several of each