Curious if prior to this potential fix you noticed a difference in prevalence of shimmy when the truck was fully laden with passengers or gear, or if it appeared upon warm up but not once the truck/tires were fully warmed?
My Hail Mary - need help diagnosing this shimmy / vibration (1 Viewer)
- Thread starter trudd
- Start date
-
- Tags
- cabin shimmy shimmy tires vibration
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
Wondering if this did the trick?
I think this is the first time I've heard of a drive shaft out of balance (on relatively newer 200-series). And both front and rear?
Hard to image it came out of the factory like that. Wonder if there's an incident, maintenance, or wear we can learn from? Any evidence if these were greased in their lifetime?
bloc
SILVER Star
My 80 had no signs of body damage, but both driveshafts had a ~5-10° twist in them, which can have out of balance symptoms when the shaft is installed in a location that it bends.. our front driveline we probably wouldn't notice. I didn't remember to ask whether it indicated happening under drive or coast.
I do think the driveline shop said it happens more often than you'd think, though they didn't know how it seems to happen. My guess was someone putting the truck into park prematurely or dropping into gear from neutral with rpms up.
- Thread starter
- #24
We had 1,600 miles of flawless performance all through west Texas through northern New Mexico mountains. Fully loaded with two adults, 3 kids, two full coolers, 10gal water, luggage. Towing a small camper weighing maybe 2,300lb loaded.
It was damn smooth, y’all. AHC really shined in a way I hadn’t felt before.
Still awaiting verdict on daily driving without a trailer. There is definitely some improvement in terms of drive quality, I just need more time in the seat and in varied conditions. The surface roads I frequent in Austin suck for any car. I’m also going to borrow a buddy’s LX for some A/B comparison.
Re: driveshaft history. No major wrecks (maybe a fender bender from PO and I gracefully hit a deer with the front DS bumper). I’ve had the car since 137k and greased the zerks for the first time around 167k. No mention of it in the limited dealer history. Remember, I had all u-joints replaced two months ago due to play. Driveshaft was probably neglected for longer than just my ownership.
It was damn smooth, y’all. AHC really shined in a way I hadn’t felt before.
Still awaiting verdict on daily driving without a trailer. There is definitely some improvement in terms of drive quality, I just need more time in the seat and in varied conditions. The surface roads I frequent in Austin suck for any car. I’m also going to borrow a buddy’s LX for some A/B comparison.
Re: driveshaft history. No major wrecks (maybe a fender bender from PO and I gracefully hit a deer with the front DS bumper). I’ve had the car since 137k and greased the zerks for the first time around 167k. No mention of it in the limited dealer history. Remember, I had all u-joints replaced two months ago due to play. Driveshaft was probably neglected for longer than just my ownership.
- Thread starter
- #25
Generally speaking, the vibrations were semi-variable in intensity and occurrence. As if something was generally out of sync, but would occasionally come back into sync here & there.
It would definitely happen when the car was fully warmed. Our previous road trip (family only, no towing) was 4+ hours of highway and we experienced it the entire time (even my wife noticed!). On that particular trip, it disappeared when going over 80mph.
- Thread starter
- #26
1 month update: I believe balancing the driveshafts did solve a rotational vibration issue, but I'm still getting intermittent bounce/looseness from the rear.
My attention is back on AHC. The LX drove great while hauling a load (5 people, camping gear, 2300 lb camper trailer). Unloaded, the bounciness comes back from time to time.
When it's bouncy, sometimes I'll put the vehicle into High mode to get the system to max pressure, and then let it go back to Neutral at 20mph. In many cases, this helps. Something about the increase in pressure (either due to towing+cargo weight or putting it into H) improves ride quality.
Why is that?
AHC history recap:
I got Techstream working last week, so that's a new tool in the kit. I've found info spread all throughout the mega AHC thread, but haven't dug up a good Techstream AHC 101 source yet.
And the ultimate hail mary: I have stock LC springs/shocks I can drop in if I really go off the deep end. That's the last resort. I really like AHC.
My attention is back on AHC. The LX drove great while hauling a load (5 people, camping gear, 2300 lb camper trailer). Unloaded, the bounciness comes back from time to time.
When it's bouncy, sometimes I'll put the vehicle into High mode to get the system to max pressure, and then let it go back to Neutral at 20mph. In many cases, this helps. Something about the increase in pressure (either due to towing+cargo weight or putting it into H) improves ride quality.
Why is that?
AHC history recap:
- Installed 4 new globes, total fluid swap, and lots of bleeding done 5 months ago.
- I did have recurring problems with air bubbles at first, which is confusing because I don't have fluid leaks in my system. How is the air getting in if fluid can't get out?
- I've done a few random bleeds since then. Sometimes there are a few tiny bubbles, sometimes not.
- the rear driver globe was totally busted. the membrane simply failed.
- I don't know when it failed. It could have been before my ownership @ 137k.
- Because the globe had failed, I wonder what other parts were under increased stress that need to be inspected/replaced. Shocks? Valves?
I got Techstream working last week, so that's a new tool in the kit. I've found info spread all throughout the mega AHC thread, but haven't dug up a good Techstream AHC 101 source yet.
And the ultimate hail mary: I have stock LC springs/shocks I can drop in if I really go off the deep end. That's the last resort. I really like AHC.
How are your rear lower control and lateral rod bushings?
Replace the AHC shocks.
I appreciate your systemic approach to finding the issue. The more I think about this, the more I tend to think it's necessary to replace the shocks. Not so much due to the internal seals and valve stack, but because of the external bushings.
Any shock has rubber bushings on the mounts and these are susceptabible to long term wear. Not that 169k is too much, but because of the history of failed accumulators, this puts excessive loads on the shocks as a blown accumulator is can create huge loads and forces as it no longer has compliance and is hydrolocked to a degree.
It's the bushings in the shock that are responsible for fine NVH.
Anatomy of an AHC shock
Fronts Measuring from center of eyelet to shoulder of shock piston Compressed - 18.75" Extended - 24.5" Monotube. 5.75" travel. 30mm shaft with internal oil passage. 43.5mm piston. 54.5mm shock body. Lower bushing - 16mm bolt hole, 53mm bushing shell Has internal valving. ~11 element...
forum.ih8mud.com
- Thread starter
- #29
Replace the AHC shocks.
I appreciate your systemic approach to finding the issue. The more I think about this, the more I tend to think it's necessary to replace the shocks. Not so much due to the internal seals and valve stack, but because of the external bushings.
Any shock has rubber bushings on the mounts and these are susceptabible to long term wear. Not that 169k is too much, but because of the history of failed accumulators, this puts excessive loads on the shocks as a blown accumulator is can create huge loads and forces as it no longer has compliance and is hydrolocked to a degree.
It's the bushings in the shock that are responsible for fine NVH.
Anatomy of an AHC shock
Fronts Measuring from center of eyelet to shoulder of shock piston Compressed - 18.75" Extended - 24.5" Monotube. 5.75" travel. 30mm shaft with internal oil passage. 43.5mm piston. 54.5mm shock body. Lower bushing - 16mm bolt hole, 53mm bushing shell Has internal valving. ~11 element...
Makes sense, that's exactly where my mind was headed next.
I'm looking through @nwfl4runner's rear suspension rebuild guide. A few shops and have inspected the bushings and ball joints and said they were fine from what they could see without removal. I'd love to replace every bushing and joint on the rig, but will probably just address the shocks for now.
Does this look like everything I need to address the 4 shocks? I'll get spare AHC fluid, of course.
Rear Shocks
Shocks (L/R) - 48530-69415 x2
Shock Bracket (top) - 48539-60020 x2
Shock Bracket (bottom) - 48505-60060 x2
Front Shocks
Retainer, Shock Cushion (L/R) - 4859760110 x2
Front Sub-Assy (L/R) - 4860960080 x2
Front Shocks (L/R) - 4851069355 x2
Front Cushion, NO.1 (L/R) - 9094801097 x2
nwfl4runner
GOLD Star
Those are the bushings you'll need. Are you running with rear seats folded up or down? Spare tire still underneath or empty?
- Thread starter
- #31
Rear seats - both positions, depending on if I'm hauling stuff or additional kids.
Spare tire lives underneath.
32cls6speedmt
SILVER Star
FYI. I would like to have my struts and mounts replaced. So I have been purchasing parts in the mean time.
I don’t have any issues yet. I do have a small leak front shock and rear shock. 13 lx with 152k miles.
The front struts and mount replacement is 4 hours of labor.
The rear struts and mount is 3 hours worth of labor.
Do you rotate your tires? Wondering if you have front tire cupping.
- Thread starter
- #34
Yep. 5 tire rotation every 5k-ish miles
- Thread starter
- #37
This thread? - SOLVED - Weird behavior / steering wobble
And your solution was replacing the Panhard bar in post #33?
From post #33:
It'll be easier if you talk to me me like a dum dum head. I'm not as knowledgeable as most of y'all!
- Dragging your rear axle means what exactly?
- The OEM panhard was.... too short? bent? bad bushings?
- The new Panhard is better because it is..... adjustable? Made in 'murica?
- Does the new panhard drop into the existing brackets?
@TeCKis300 - curious your thoughts on panhard theory. Seems like shocks are still worth replacing first?
Hey yes that one. And yes, you probably need to level your system on a 4 wheel alignment rack.
If you are stock then something may have shifted sensor wise, or even worse, maybe the rear left shock is weeping.
That can happen because of another design flaw actually.
AHC isnt a well designed articulating suspension. Its a fantastic suspension slapped onto an unmodified 5 link.
Do you ride loaded up or empty in the rear?
Teck knows i love him but this ^ right here is why im off forum for months at a time.
Its not a theory if its fully figured out and solved, but then again, i do own a lemon LX.
If you are stock then something may have shifted sensor wise, or even worse, maybe the rear left shock is weeping.
That can happen because of another design flaw actually.
AHC isnt a well designed articulating suspension. Its a fantastic suspension slapped onto an unmodified 5 link.
Do you ride loaded up or empty in the rear?
Teck knows i love him but this ^ right here is why im off forum for months at a time.
Its not a theory if its fully figured out and solved, but then again, i do own a lemon LX.
- Thread starter
- #39
Well, for the sake of everyone here, you should just ignore Teck's response if he takes the bait
I'm just as likely to take both y'all's advice as I am to ignore it and blow that money on college for the kids.According to an indie shop, a Cruiser specialist, and Lexus dealership: my shocks aren't weeping, but I imagine something took the additional force created by the busted rear left accumulator globe that I replaced.
I'm mostly empty in the rear. Usually have 3 kids in the middle row, sometimes their friends hop in the 3rd row. Occasionally tow a small 2,300lb camper and a week of food/ice/drinks.
I still don't have a fundamental understanding of what the panhard solved for you, but that's probably on me. I'll spend more time in your thread and doing some research. I still have a lot to learn about what each of these components controls independently vs. how they work together to determine drive quality.
Well, for the sake of everyone here, you should just ignore Teck's response if he takes the bait
According to an indie shop, a Cruiser specialist, and Lexus dealership: my shocks aren't weeping, but I imagine something took the additional force created by the busted rear left accumulator globe that I replaced.
I'm mostly empty in the rear. Usually have 3 kids in the middle row, sometimes their friends hop in the 3rd row. Occasionally tow a small 2,300lb camper and a week of food/ice/drinks.
I still don't have a fundamental understanding of what the panhard solved for you, but that's probably on me. I'll spend more time in your thread and doing some research. I still have a lot to learn about what each of these components controls independently vs. how they work together to determine drive quality.
No thats my bad. Forgot to answer that bit.
Yes, its from the rear axle being out of plane, because of a fixed panhard, in my case due to lifting etc.
In yours, most likely due to sag, blown globe, and a weak shock on the left side which is now probably compromised.
Because of.. drumroll. Design flaw lol
You would also do my patented rear spring mod bc that is just wrong off the factory floor.
I am somewhat of a pioneer here,
