10ga
New member
I thought the front diff was the weak spot and the ARB diff alleviates this? Just curious what else might be a problem?
There's no problem locking the front diff on a 100 series. I know several guys that have both front and rear lockers on their 100. It's actually a lot better, especially if you go with the ARB because it ads extra strength to the front diff and you're not having to nail it to get out of a bad situation. The 98 and 99 100 has 4 spider gears in the carrier and starting in 2000, they have 6 spiders, so there's much more surface area of gear teeth in contact with each other and less likely to be a problem. In other words, if you have a 98 or 99, I would get an ARB front locker if I was going to do a lot of serious off-roading. I've about gave up on finding a decent FJ80 and I'm starting to look for a 100 again. I'm hoping to find a 98 or 99 and put an air locker in the front. Getting the 98 or 99 with the rear factory locker will save me $1200 putting in an ARB in the rear.
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