Lets rewind back a couple days. When I woke the 4Runner up after the power steering repairs both of the Die Hard Platinum batteries were dead. Like 8V dead. I charged them up and we seemed to be good to go. When we took the truck out over the weekend, we didn’t have any problems except when we stopped at the gas station on the way home. I charged up the batteries again thinking those had to be the issue. With the batteries holding, I took off for work this morning in the truck since I needed it to pick up the Camry wheels. Well about a third of the way there I noticed our voltage was just getting lower. Time to turn around while we still have some juice to get home.
When I swapped the engine there was what we will call a mishap with the original alternator. Luckily the engine came with a spare so we swapped that in at the time. I think it’s now time to swap that out. I’ve known I was on borrowed time for a while trying to run electric fans, dual batteries, a fridge, and aux lighting all off of 80 amps. A quick search online found the common GM “upgrade”, or that LCE Engineering offers a 160 amp upgrade. It’s $300 and has a wait time since they are built to order. This wasn’t helping me out today.
We still have a complete 3UZ swap sitting in the shop so I popped the Alternator off of that.
A quick comparison to my original alternator revealed a few things. The main tab is the right thickness, and places the pulley at the right depth for the belt to line up. Another plus is that the plug is correct to plug directly in to the factory harness. The other tab however is completely in the wrong spot. Something would have to be fabricated. Lets see if its worth it. Rock Auto said the GS alternator put out 100 amps. More but not by a lot.
A little more searching found that the LS430 and SC430 looked to be a similar mount but bumped the output up to 130 amp. This might be worth it. I jumped on Car-Part.com and found a source for one locally. I ended up at $80 after they doubled the price with a “core charge” when I go there, but still not a bad price for the out put. Time to make it fit.
The LS alternator comes apart really easy and allows that front case to come off. Above you see it sitting on the original alternator to see how far you have to move the bolt hole.
First I welded a tab onto the case. I drilled a 1″ hole in the tab and machined a bushing on the lathe that allowed me to set the depth the same as the 4Runner one. I clamped a brace across the original tab to square everything up before welding.
Don’t judge me too harshly on the welding, this is only the second time I’ve welded aluminum with a TIG.
I removed the extra tab (it runs into the dipstick tube if you don’t) and reassembled the alternator.
I ended up needing to re work the lower bracket in the 4Runner to both clear the original bolt hole on the alternator and accommodate the large size of the new unit. The wiring connections are moved from the original position but everything reaches. The original alternator has a stud size of 6mm, and the new one jumps up to 8mm so my factory wiring had to be drilled out until I can upgrade the wiring to match.
