I Destroyed The AHC Rear Height Sensor. (1 Viewer)

[GTV]

Today I thought I'd toss in the extra pair of 5mm coil spacers I've had kicking around. No big deal, I've been in there before. The job went as planned so I started the truck up and started playing with the AHC buttons. The front was doing its thing but the rear was very low and not doing a damn thing. I figure something has to be up with the rear height sensor so I take a look. First thing I see is that the upper part of the arm is twisted up and the lower is far too close to the upper control arm, the elbow had gone over center. I start moving things around and realize the sensor bracket is seriously bent, as if it were almost pulled off the frame! So off it comes, I'm getting it back reasonably close to its original configuration, though still not straight enough to bolt it back on easily. The upper arm needed to come off so the sensor could be removed from the bracket to be put in a vise. And that's when the stud on the sensor snapped off. Game over.

Like I said, this thing was seriously messed up, I should have taken a before pic but I wasn't in the mood. I don't know how I managed to do this, like I mentioned I've successfully performed this task before. Obviously when I lowered the axle it pulled everything down. When the upper arm rotated it hit the stop on the bracket- and plowed it straight out of the way (it's sorta straightened in the pic above). The part of the bracket that holds the wire was folded twice in on itself, the 90° was about 30° and it bent again right where that U shaped plastic thing is screwed to and broke it into the three pieces there. What is that thing there for anyway?

Annoyingly I have one 1700 miles away tucked in storage. I've already been through the classifieds but if anyone has one for sale and can ship it to New Mexico asap I'd really appreciate it. I promise I'll be nicer to it than I was this one.

 

[suprarx7nut]

Today I thought I'd toss in the extra pair of 5mm coil spacers I've had kicking around. No big deal, I've been in there before. The job went as planned so I started the truck up and started playing with the AHC buttons. The front was doing its thing but the rear was very low and not doing a damn thing. I figure something has to be up with the rear height sensor so I take a look. First thing I see is that the upper part of the arm is twisted up and the lower is far too close to the upper control arm, the elbow had gone over center. I start moving things around and realize the sensor bracket is seriously bent, as if it were almost pulled off the frame! So off it comes, I'm getting it back reasonably close to its original configuration, though still not straight enough to bolt it back on easily. The upper arm needed to come off so the sensor could be removed from the bracket to be put in a vise. And that's when the stud on the sensor snapped off. Game over.
View attachment 2911680
Like I said, this thing was seriously messed up, I should have taken a before pic but I wasn't in the mood. I don't know how I managed to do this, like I mentioned I've successfully performed this task before. Obviously when I lowered the axle it pulled everything down. When the upper arm rotated it hit the stop on the bracket- and plowed it straight out of the way (it's sorta straightened in the pic above). The part of the bracket that holds the wire was folded twice in on itself, the 90° was about 30° and it bent again right where that U shaped plastic thing is screwed to and broke it into the three pieces there. What is that thing there for anyway?

Annoyingly I have one 1700 miles away tucked in storage. I've already been through the classifieds but if anyone has one for sale and can ship it to New Mexico asap I'd really appreciate it. I promise I'll be nicer to it than I was this one.

I've heard that's a risk (along with tugging brake lines and cables), but I've never had to mess with the AHC sensor. Must just take the wrong sequence and amount of flex during the job to push that beyond its limit.

Hope you get it back to 100% quickly!

 

[Red Beard]

Today I thought I'd toss in the extra pair of 5mm coil spacers I've had kicking around. No big deal, I've been in there before. The job went as planned so I started the truck up and started playing with the AHC buttons. The front was doing its thing but the rear was very low and not doing a damn thing. I figure something has to be up with the rear height sensor so I take a look. First thing I see is that the upper part of the arm is twisted up and the lower is far too close to the upper control arm, the elbow had gone over center. I start moving things around and realize the sensor bracket is seriously bent, as if it were almost pulled off the frame! So off it comes, I'm getting it back reasonably close to its original configuration, though still not straight enough to bolt it back on easily. The upper arm needed to come off so the sensor could be removed from the bracket to be put in a vise. And that's when the stud on the sensor snapped off. Game over.
View attachment 2911680
Like I said, this thing was seriously messed up, I should have taken a before pic but I wasn't in the mood. I don't know how I managed to do this, like I mentioned I've successfully performed this task before. Obviously when I lowered the axle it pulled everything down. When the upper arm rotated it hit the stop on the bracket- and plowed it straight out of the way (it's sorta straightened in the pic above). The part of the bracket that holds the wire was folded twice in on itself, the 90° was about 30° and it bent again right where that U shaped plastic thing is screwed to and broke it into the three pieces there. What is that thing there for anyway?

Annoyingly I have one 1700 miles away tucked in storage. I've already been through the classifieds but if anyone has one for sale and can ship it to New Mexico asap I'd really appreciate it. I promise I'll be nicer to it than I was this one.

I have that exact part. But I’m all the way in Philly. I could ship it to you after work today.

For what it’s worth, I drove a while with a broken sensor linkage in the front. But I’m not sure if what you have is salvageable?

 

[GTV]

I've heard that's a risk (along with tugging brake lines and cables), but I've never had to mess with the AHC sensor. Must just take the wrong sequence and amount of flex during the job to push that beyond its limit.

Hope you get it back to 100% quickly!

In hindsight I was trying to do the job a bit quick and lazy this time. I kept the back up on a high lift floor jack (jack stands under for insurance) and I removed the lower shocks without supporting the axle and gently letting it down with a floor jack from underneath. I do remove the brake line clip where the soft line meets the frame, it gives some much needed slack and prevents it from damage. I'll be more careful next time!

I have that exact part. But I’m all the way in Philly. I could ship it to you after work today.

View attachment 2912098


For what it’s worth, I drove a while with a broken sensor linkage in the front. But I’m not sure if what you have is salvageable?

Other than the arm I don't think what I have left is salvageable. The bracket is a mess and I don't trust the sensor after being turned so far, even if I could attach the arm. Luckily I can live without my truck for a few days, if I needed to I might try to plug the sensor back in and lock it in place, that might raise the back up if the sensor isn't FUBAR.

Thank you for the offer on the sensor, it looks like another mud member and a FB 100 series group member are each sending me theirs so I'll have a spare on hand (in the truck this time!). I'll let you know if I need yours.

 

[GTV]

The sensor from the guy on the UZJ100 group on FB arrived yesterday, it's from an '01 with about 200k on the clock. I swapped my lower arm over since it had marginally better boots and was the only component that wasn't trashed.

Dragging ass

And Robert's your father's brother, $12 for shipping and I'm back in business!

I didn't get real particular with adjusting the rear height. First time was way too low, second was close enough. I currently don't have a proper shop to wrench in so my patience for tinkering is low. The rear might need to come up a little still but I need to get Techstream on there to see where my numbers are. I'm pondering putting my hub to fender measurements back to stock as long as I'm rolling these little 33's. Considering I have less than 17k miles on these and I do a 5 tire rotation I'm going to be stuck with them for a while.

 

[AtoyotA]

anybody with an AHC FSM know the torque spec on the rear sensor adjustment bolt? i adjusted mine yesterday and after seeing this am worried if my guten-tight method was too much.

 

[AtoyotA]

never mind i found it. it's 49 in lb