Bump steer and tie-rod end flip

[ramangain]

Other comment is that setting AHC pressures below spec to pre-compensate for heavy interior weights and trailer towing isn't necessary. If you need additional compensation at the rear to keep AHC functional when towing a heavy trailer, helper airbags in the rear springs and/or a weight distribution hitch are the known, proven answers.

You may also find that the ride will improve if you raise your AHC pressures to the bottom end of the spec.

 

[gatormark91]

I had the same issue and needed to replace the rack.



BAD idea. As $hitty as it is to replace the rack, you only want to do it once. Good chance the DA rack starts leaking within 10k miles. OEM or bust.

+1 on not buying from Detroit Axle. Many bad experiences with them. I think they still owe me $75 that I'll never get back.

 

[krispykritter]

Other comment is that setting AHC pressures below spec to pre-compensate for heavy interior weights and trailer towing isn't necessary. If you need additional compensation at the rear to keep AHC functional when towing a heavy trailer, helper airbags in the rear springs and/or a weight distribution hitch are the known, proven answers.

You may also find that the ride will improve if you raise your AHC pressures to the bottom end of the spec.

It's not (wasn't, anyway) out of spec, just at the bottom end of the spec. I'm checking everything now to see where it is today.

 

[JunkCrzr89]

Which tells me a different part number and it's discontinued.

Dude, no offense intended but you gotta read. For the 100 series, 9 times out of 10, if a part number is discontinued it’s because it was replaced by a different part number. Rarely are 100 series parts NLA. Part numbers get superseded all the time.

Unfortunately, it's already been shipped.

Send it back.

 

[JunkCrzr89]

+1 on not buying from Detroit Axle. Many bad experiences with them. I think they still owe me $75 that I'll never get back.

@knewstance Detroit rack started leaking not long after install…and now he’s having to do the job again…with an OEM rack.

 

[krispykritter]

Dude, no offense intended but you gotta read. For the 100 series, 9 times out of 10, if a part number is discontinued it’s because it was replaced by a different part number. Rarely are 100 series parts NLA. Part numbers get superseded all the time.

Okay - offense intended, I can read fine, and saw that the new part number superseded the old. My question was how you found that part number in the first place. When I searched for it, all I found was the old part number that showed discontinued on quite a number of toyota parts sites with no mention of the new part number.

If offense isn't intended, maybe don't say something offensive?

Other comment is that setting AHC pressures below spec to pre-compensate for heavy interior weights and trailer towing isn't necessary. If you need additional compensation at the rear to keep AHC functional when towing a heavy trailer, helper airbags in the rear springs and/or a weight distribution hitch are the known, proven answers.

You may also find that the ride will improve if you raise your AHC pressures to the bottom end of the spec.

So as it turns out, my front pressure was very low out of spec - around 5.4 mpa when it should be around 6.4 at the low end of the spec. I KNOW I set that correctly last time around and have screen shots of it. Not sure how I managed to get that far off the low spec, but I've adjusted the rake back to roughly an inch and the front AHC pressures back up to 6.6 mpa in neutral. It's still lifting alot but it feels more controllable than it did. I'm going for a drive to Home Depot soon so I'll be able to plant it up to a decent speed and see how it feels.

I can definitely see toe in remaining but maybe it's just the looseness in the rack at this point. Seems like the nastiness was a product of a number of things as suggested near the start of this thread.

 

[ramangain]

For comparison, I keep front AHC pressure at 6.7. I use rear airbag helper springs (helps trailer hitching) and WDC hitch when towing. Hauls 7k lbs. trailer just fine, but slow. Rides just fine.

No clue if I suffer WOT from stationary bump steer like you. I don't drive in that way.

 

[JunkCrzr89]

Okay - offense intended

If offense isn't intended, maybe don't say something offensive?

Welp, that’s my cue. Good luck with the squatter!

 

[krispykritter]

For comparison, I keep front AHC pressure at 6.7. I use rear airbag helper springs (helps trailer hitching) and WDC hitch when towing. Hauls 7k lbs. trailer just fine, but slow. Rides just fine.

No clue if I suffer WOT from stationary bump steer like you. I don't drive in that way.

I have an F150 that I use for towing anything heavier than my camping trailer which weighs in around 2200 lbs max. For the F150 I have a WD hitch and usually put about 8500 lbs behind it with 1030 lbs on the tongue. That is also competent but slow! I agree, if I was towing what you do, I'd be using airbags to help support the weight!

I also don't generally floor it, but I want it to behave when I do. These changes have made quite the difference at keeping the suspension in its happy place and out of the extreme bump steer range! I appreciate the input.

 

[ramangain]

ALL of us are here to try and help.

 

[krispykritter]

ALL of us are here to try and help.

... Unsure if telling me I 'need to read' is helpful, particularly when he didn't read the actual question I asked.

I'm not here to piss people off; I'm here because, generally, this is the best source of knowledge about the 100 series.

Yall have helped with my issue. I've learned more about my truck. As stated numerous times, I appreciate the assistance.

 

[Joe422]

So, I've ordered a new steering rack from Detroit Axle. Hopefully, that eliminates some of the ridiculous toe in I get under throttle. I'm also planning to double check my AHC pressure tomorrow sometime.

Hows the Detroit Axle Steering rack holding up for you? Any comments about it?

 

[Joe422]

... Unsure if telling me I 'need to read' is helpful, particularly when he didn't read the actual question I asked.

I'm not here to piss people off; I'm here because, generally, this is the best source of knowledge about the 100 series.

Yall have helped with my issue. I've learned more about my truck. As stated numerous times, I appreciate the assistance.

I know, its an old topic, but regarding the St Rack availability... the older version is available for about $650 ish, from the dealer.
This it the one that uses 1 big bolt and a clamp to secure.

My '04 and likely your '06 uses the updated St rack, which is mounted with 2 big bolts (no clamp).
This version is harder to find, and when you do find an OE one, prices are in the $1150 range.

I dont have the actual part numbers in front of me, but this was what all my research found.

 

[krispykritter]

Hows the Detroit Axle Steering rack holding up for you? Any comments about it?

Funny you should mention that. I haven't actually installed it or returned it. After determining my rack was fine I decided to just hang on to it until I have an issue. I'm at 171k miles so it can't be too much longer before I need to replace it.

You're correct, mine uses the two bolt variety. New bushings solved my rack movement problem but I still have pretty wild bump steer. It's all in the front end travel and there's not much I can do about it unfortunately.

 

[Bisho]

Funny you should mention that. I haven't actually installed it or returned it. After determining my rack was fine I decided to just hang on to it until I have an issue. I'm at 171k miles so it can't be too much longer before I need to replace it.

You're correct, mine uses the two bolt variety. New bushings solved my rack movement problem but I still have pretty wild bump steer. It's all in the front end travel and there's not much I can do about it unfortunately.

I’ve got 260k on mine, so it could be a while.

 

[Joe422]

Haha.. interesting. Well, in our group of friends, there's 3 Hundy's and 2 of them recently (in the past yr) replaced their st racks... I believe with OE racks.
One was leaking, and had odd handling, and the other actually "exploded" and lost power steering. These were also the older racks (1 bolt/clamp).

My '04 (2 bolt) rack had a some leak inside the tie rod boot, but felt fine for the most part... and the fluid level never goes down. I also put in some 205 just in case.
I already purchased the Detroit Axle rack as well.. and its sitting on my shelf as a backup, but the stock rack is still going... at 273k+ miles.
I did have to replace the bushings a couple yrs ago, and recently replace the inner/outer tie rods and the boots. So far feels fine, and the Detroit Axle rack will remain as a emergency backup. I'd love to find a new OE rack someday, but dont think it's gonna happen for under $1k. Maybe shop for it again around Blk Fri deals. Who knows.
Oh, and I did pick up the OE rebuild kit too... so that throws in another option, but only time will tell for now.

 

[krispykritter]

To bring back a slightly contentious thread - I finally installed OEM non-AHC t-bars along with nitro UCAs. I spun the adjusters all the way out before installing the new t-bars. Once back on the ground, I needed to add two rotations to the bars to get my front pressures to around 6.5 mpa.

I can say that they do stiffen things up. So far I haven't been able to drive it all that far but it doesn't feel uncomfortably stiff so far - it feels like it's more matched to the increased spring rate with the kings, honestly.

Theory is - less twist/preload in the thicker t-bars means they unload quicker as the CG shifts backwards, decreasing pitch.

But - I can tell you, my carolina squat problem is gone. Completely. Floor it, and it pitches up a little and just goes. It's so nice to be able to use full throttle when needed! Way less pitch under braking and acceleration makes for a much better ride. I'll try to drop some feedback in a couple weeks but so far I'm very happy with the change.

No more carolina squat = no more bump steer. On the street at least!

Edit: Reference info for those of you still running AHC and having similar issues: my LX weighs around 6150 lbs sitting in the driveway with some tools (~100 lbs) in a plywood drawer setup, a 35L Engel fridge, hidden winch, and rock sliders. I have shock spacers for the ahc system.

My hub-to-fender heights are about 21 inches front and 22 rear. With 33's, that makes ground to fender measurements around 36.25 inches front and 37.25 inches rear.

Edit edit: nitro UCAs with added AHC bracket: