Well, it’s been an expensive couple weeks!
I’ll start out with the fact that both rear axle shafts are bent on the 4Runner. I have guessed one was a little bent for a while, but now it seems both are bent. I think it’s time for a little trip down memory lane (Sorry, this is going to get long).
When I ran Wheeler Lake last fall it was the first real wheeling trip in the 4Runner; it’s not a super hard trail, but with 8” of fresh wet snow things get a whole lot harder. I did not have my ARB compressor installed, so I was still open in the front. There was a nasty little ledge that was covered in snow, I got the front of the 4Runner on the ledge but I had to give it a little bump to make it all the way up. The rear of the 4Runner bounced a little harder than I like, but I didn’t think anything of it. Hell, I’ve jumped the crap out of my old green 4Runner and never bent a shaft (the housing yes, but not an axle shaft).
After that the rear brakes were making some odd noises, but I figured it was just ice building up inside the drum from the water crossing and I ignored it for the rest of the day. The following day I was driving the 4Runner and the rear brakes seemed a little “jumpy”, I still had stock front rotors which were a little warped so I didn’t notice anything in the pedal. So I replaced the shoes, drums and hardware kit; something still didn’t feel right but it was hard to pinpoint with the balance of the MTR’s.
I noticed some vibration in the rear brakes after the Tundra swap; the old front rotors were warped like crazy so I didn’t know what was going on until after I replaced them. It’s a long story with little clues/issues along the way, but it all makes since now. It’s clear the driver side rear axle has been bent since Wheeler Lake, and after Holy Cross it just got worse. I think that’s when I slightly bent the second axle (not as bad); I didn’t beat on the 4Runner, but I did baja down Shrine Pass and there were a couple potholes I couldn’t stop for. Between the weight of all my gear and the tongue weight of the trailer it must have done the trick.
The vibration while driving and braking was really bad, or not so bad at times. It was confusing, but I realized that having an open diff would change the relationship between the two axles; at times the axle shafts are in sync and shake like crazy, after a turn they cancel themselves out and it’s not so bad. I was really in disbelieve, but after doing some searching it looks like this is a fairly common thing on 3rd Gen 4Runners and Tacoma’s that really get wheeled. Vermejo on Yotatech went through three rear axle shafts in a year; he had a 3rd Gen on 35’s and wheeled the crap out of his rig.
I looked for replacement HD chromo shafts, but they don’t offer them for the 3rd Gen 4Runner (just the Tacoma) and I called Poly Performance, they said the Tacoma shafts would not fit my 4Runner. So I really had two options; stock weak junkyard axles, or a full float FROR kit. After a lot of thought, and planning where I plan to take the 4Runner with the trailer, the stock axles were not going to cut it.