Is it solely road speed dependant or does your throttle input impact it all like with u-joints?
Painful low frequency drone/pressure in cabin (2 Viewers)
- Thread starter LJE
- Start date
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- Thread starter
- #262
I *think* it's all roads speed dependant. Going to spend some time on the road in the next day or two trying to rebaseline & recharacterize it after all the 'fixes' I've done.
I’m no expert on these things but is it possible that all the extra sound deadening you added is trapping the resonance in a certain part of the truck, or making it have a different frequency that is painful to humans?
Had to edit my earlier post as I had the bushing location wrong on the torsion bar crossmember. It looks like the 'support assy, front suspension' sits inside a frame crossmember. Appears the torsion bars and support assembly have to be removed to replace the bushings.
First pic below shows the support assembly with bushings circled.
Torsion bar adjustment below with bolt/bushing circled.
First pic below shows the support assembly with bushings circled.
Torsion bar adjustment below with bolt/bushing circled.
- Thread starter
- #266
Alright, update here.
Some observations (and no answers):
It's a good thing for this vehicle that I only found this after I put so much effort into resurrecting it. If I had less than $15K in it (I've got more than double that at this point with the lockers/leather/bumper/etc) I would roll it off a cliff.
Some observations (and no answers):
- It's definitely worse the higher outside temperature gets. That doesn't make sense to me, but neither does anything about this. Drove to work at ~0500 when it's 50 degrees outside - not terrible. Still there, but tolerable. Drove home at 1600 that day when it's 80 degrees outside and ow, my ears. So. Much Worse. This correlates well overall with my experience - terrible in the summer, better in the winter.
- It's better with more crap in the back. Loaded down for Cruisers on the Rockies, it was mostly tolerable. Some days on the road were worse than others, which is confusing.
- I ratchet-strapped the rear wing window mechanism to the floor D-rings to eliminate them vibrating the windows as a possibility. This actually changed things - rather than a 'pulsing' pain/pressure on your eardrums, it's now a constant pressure feeling - as if you were ascending/descending in an airplane but couldn't clear your ears. This would point to there being a pressure differential being created that was 'flapping' the rear wing windows, but with them ratchet strapped they can't do that any more; rather than a pulse you just get a constant pressure feeling on your ear drums. Still no audible noise.
It's a good thing for this vehicle that I only found this after I put so much effort into resurrecting it. If I had less than $15K in it (I've got more than double that at this point with the lockers/leather/bumper/etc) I would roll it off a cliff.
Wild shot here- What if instead of it being related to the ambient temp, it's actually something to do with whether you're running the heat or AC. Tried running with the HVAC off in the cooler/warmer duplicable conditions and seeing if the difference still exists?
This is really sounding like some sort of air intrusion/buffeting situation. How's the windshield seal/fitment? How's the sunroof seal? Window and door seals as well as rear hatch? Your last summary above makes me think that more air is entering the cabin than can escape the cabin...but from where?! The mention of the loaded rear made it better slightly......muffler tone or vibration?
- Thread starter
- #270
Alright, coming back to this thread after a couple months.
Problems still persist - I've swapped the front door weather sealing (both doorside and body side), and the main rear hatch stripping. No change. Next parts sale I'll grab the rear door seals and the seal that goes between the rear hatch and tailgate.
I pride myself on critical thinking and tough troubleshooting skills - but I just can't find a correlation here.
Some days it's 'OK', some days it's awful. Often time it's almost 'ok' in the morning, and bad on the drive home from work. Outside temperature seems like maybe the only strong correlations that I can find, but I don't know what would cause that.
One thing that I need help from the community on (and please, don't go off memory here - do me a favor and test this out!).
When I discovered this, I had the thought that maybe the engine intake was somehow creating a vacuum in the cabin. I pulled the fender well liner off and drove around like that for a while, no change to the ear pain & no change to the noise coming from between the headliner and roof when the sunshade is opened. I don't know what would cause this noise, but since I've been grasping at straws for over a year now I'd just like to know if this is something that everyone's vehicle does.
I did have the injectors cleaned/checked by FIS in CO (I had 'DIY' cleaned them at home when I built the engine, and the report from FIS actually came back really good before they even did any cleaning, so that was nice to see I guess). I'm also going to swap the fuel pump because I've had a couple long cranks. No sort of weird fuel trims though, so I don't think it's affecting engine performance.
Right now the plan is to take this to the Car Care Nut (~4 hour drive) from me sometime this winter. I hate that idea - I've done the hard diagnostic thinking. I've gone through all the information that I can find. I've resorted to the parts cannon at this point, but something is still wrong & at this point it's going to take someone with more experience than I have to find & correct it.
(especially before I yank the TRD supercharger off 2UZ 4runner I bought for $1800 and drop it on the LX, hah).
Problems still persist - I've swapped the front door weather sealing (both doorside and body side), and the main rear hatch stripping. No change. Next parts sale I'll grab the rear door seals and the seal that goes between the rear hatch and tailgate.
I pride myself on critical thinking and tough troubleshooting skills - but I just can't find a correlation here.
Some days it's 'OK', some days it's awful. Often time it's almost 'ok' in the morning, and bad on the drive home from work. Outside temperature seems like maybe the only strong correlations that I can find, but I don't know what would cause that.
One thing that I need help from the community on (and please, don't go off memory here - do me a favor and test this out!).
- Open your sunroof shade (but leave the sunroof closed)
- Get up to 30-40 mph
- Punch the gas
- Listen
When I discovered this, I had the thought that maybe the engine intake was somehow creating a vacuum in the cabin. I pulled the fender well liner off and drove around like that for a while, no change to the ear pain & no change to the noise coming from between the headliner and roof when the sunshade is opened. I don't know what would cause this noise, but since I've been grasping at straws for over a year now I'd just like to know if this is something that everyone's vehicle does.
I did have the injectors cleaned/checked by FIS in CO (I had 'DIY' cleaned them at home when I built the engine, and the report from FIS actually came back really good before they even did any cleaning, so that was nice to see I guess). I'm also going to swap the fuel pump because I've had a couple long cranks. No sort of weird fuel trims though, so I don't think it's affecting engine performance.
Right now the plan is to take this to the Car Care Nut (~4 hour drive) from me sometime this winter. I hate that idea - I've done the hard diagnostic thinking. I've gone through all the information that I can find. I've resorted to the parts cannon at this point, but something is still wrong & at this point it's going to take someone with more experience than I have to find & correct it.
(especially before I yank the TRD supercharger off 2UZ 4runner I bought for $1800 and drop it on the LX, hah).
I haven't read through this entire thread, but have you had somebody "tape" you in, as in tape every door jam, body line, and window up? I'm thinking, based on the last 60 seconds of read time, that it could be a air flow disturbance and potentially multiple things creating this (perfect combo of old seals, a gap, misaligned door stiker, hood, etc)
I would even tape the rear air outlets on the D Pillar, and potentially the HVAC Intake right by the windshield. If it goes away, remove one section of tape at a time until it comes back. If you think it's a pressure issue
I would even tape the rear air outlets on the D Pillar, and potentially the HVAC Intake right by the windshield. If it goes away, remove one section of tape at a time until it comes back. If you think it's a pressure issue
I really respect the effort you have put into this problem. The "taping in" is an interesting idea. Why not? Cheap test. Also, I go back to early in this thread when I mentioned body panels loose on Sprinter Vans causing droning at highway speed. Another cheap idea would be to get a fairly large magnet(s) placed in a sock and randomly placed around your Cruiser to add weight to eliminate possible body panel buffering. Just another possible idea. Really appreciate your tenacity here!
Also, I never replied to you about the nice camera mount you made for me. Thanks!
