Strange alternator woes

[vanroth]

Had to do a quick recovery on my '06 Montero while heading to dinner tonight. Thankfully the truck made it to the parking lot before the battery gave up the ghost.

The dilemma: I'm about to be on my 4th alternator in the last 20K miles. The truck is otherwise immaculate condition with nary the mechanical issue and only 75k miles. Admittingly the last two alternators where not original Mitsubishi units, but still I would have expected them to last longer. I typically do not get much warning before they go -- by the time the truck starts reporting low voltage, most everything starts to shutdown.

Anyhow else had this issue? Is there a "Mean Green" equivalent? Thank goodness it takes only a few minutes to change them out but I've been close to being stranded a couple of times now.

Regards,
vanroth

 

[vanroth]

I should ask now as it will be easier than carrying a spare alternator for next time -- any recommended Montero Limited dual battery mounts/kits?

 

[Salonika]

Oil leaking on it? That will kill them quickly.

 

[vanroth]

Oil leaking on it? That will kill them quickly.

Thanks for the input. It is all bone dry and no leaks (yet!).

Two of the failures were zero charge. One of the failures was likely the regulator as it overvolted (18v).

 

[Salonika]

Check & clean all grounds and the positive lead to battery. Excessive resistance would be my next best guess.

 

[PacS14]

It's old news that aftermarket alternators for Monteros suck, I replaced the voltage regulator myself on one of those aftermarket (duralast good), it was my third in less than a year, and they were trying to deny my warranty, so I said screw it, I bought a voltage regulator on ebay and it has lasted me a few years already.

 

[vanroth]

Just an update that is not an update.

Replacement alternator came in -- wrong unit. Waiting for the replacement again. Confirmed all connections look like new.

Started working on the dual battery box and will place it by the passenger firewall. There is not a lot of room and standard tray will not fit, but a redtop should just barely fit.

 

[vanroth]

Bought another mystery Ebay (BNR) alternator. Since there are no alternatives I'll just keep a spare one in the cubby.

 

[Smileyshaun]

Most older rigs have terrible grounds that will play havoc with the electrical system . Make sure all your ground straps are in good shape .
Should have
• block to firewall
• block to frame
• battery to frame
• battery to body
• rear body to frame

With a older rig that’s maybe been taken apart before the one on the back of the block to the body usually gets broken or just forgot to be put back on . Also just because a cable looks clean on the end doesn’t mean it’s not corroded internally . Personally I just replace all of them and add a couple extra for good measure .

 

[Salonika]

Most older rigs have terrible grounds that will play havoc with the electrical system . Make sure all your ground straps are in good shape .
Should have
• block to firewall
• block to frame
• battery to frame
• battery to body
• rear body to frame

With a older rig that’s maybe been taken apart before the one on the back of the block to the body usually gets broken or just forgot to be put back on . Also just because a cable looks clean on the end doesn’t mean it’s not corroded internally . Personally I just replace all of them and add a couple extra for good measure .

This reduces resistance and stress on the alternator.