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qclabrat

Well-Known Member
I found that Delrin doesn't deform or sag like rubber, it can slightly bind and then suddenly let go with a knock. This doesn't sound like your issue though.
By loud, as if something hit the car underside like a rock. but repeatable?
Yes, not so much a knock but more of a thump as if a shock bottomed out
 

Patrick

Overthinking the draft from the basement already
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Dingo

Well-Known Member
Need to get it on a drive-on lift, this way the suspension is loaded. Then poke around while pushing up and down on the suspension.

Worst case scenario is using chassis ear. I use them as a last resort, but usually the only way to track down mystery noises.

 

alex_k

Well-Known Member
DCM is Subaru version of on star? How long did you wait for it to go to sleep
Yes, DCM (data communication module) is a part of Subaru STARLINK.

I locked a hood latch and waited about 30 min. I monitored the drain current over 2 hours yesterday, dropped voltage to 11.5V - hoped to reproduce that catastrophic discharge. That did not happen, the drain was stable around 150 mA.
 

JerseyPete

Well-Known Member
Yes, not so much a knock but more of a thump as if a shock bottomed out
How repeatable is it? If you go to an empty parking lot and place short 2x4 and run them over, can you replicate the noise? Next would be one side vs the other, then straight vs left vs right turns. Just looking to isolate the conditions in which you hear it.
 
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Karate Monkey

Well-Known Member
Some modules are part of the "loop" of data sharing, so they need to be in the loop or the other modules set codes for the missing module.

Aren't modern cars wonderful? PIA

Does the microphone still work (hands free call, Google, etc) if you pull the fuse? Inquiring minds want to know :)
 

alex_k

Well-Known Member
Some modules are part of the "loop" of data sharing, so they need to be in the loop or the other modules set codes for the missing module.

Aren't modern cars wonderful? PIA
removed the fuse, drain current wend down to 10 mA, took the car for quick drive, no warnings, seems everything still working

please pm your favorite beer and address to ship! If you work/live not far from South Brunswick I can deliver
 
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qclabrat

Well-Known Member
How repeatable is it? If you go to an empty parking lot and place short 2x4 and run them over, can you replicate the noise? Next would be one side vs the other, then straight vs left vs right turns. Just looking to isolate the conditions in which you hear it.
I think it's the same from both sides, but I get your point. Lemme find a 2x4 and empty lot this afternoon. Will report back and try to get a vid. Also going to give Speedtech a call for other suggestions to check while I'm at it
 

qclabrat

Well-Known Member
@JerseyPete ran your suggested test yesterday and it's on both sides. Can't really hear it from the first vid but in the second you can really hear the bang at the end.

I've done some more reading online and it seems adjustable coil overs are often noisy, mine are Viking Warriors and a common problem are the lock rings loosen or the top bolt need to be torqued down. I checked the lock rings and they seem tight, but not able to get to the top from underneath. I'll jack the back up this weekend, remove the wheels and look from there. Need to check the differential anyway as I noticed a whine when accelerating and @jklett thinks it's low on fluid.PXL_20210421_125834916.jpg

Is this a Ford 9" diff?
PXL_20210421_130025274.jpg
 

JerseyPete

Well-Known Member
@JerseyPete ran your suggested test yesterday and it's on both sides. Can't really hear it from the first vid but in the second you can really hear the bang at the end.

I've done some more reading online and it seems adjustable coil overs are often noisy, mine are Viking Warriors and a common problem are the lock rings loosen or the top bolt need to be torqued down. I checked the lock rings and they seem tight, but not able to get to the top from underneath. I'll jack the back up this weekend, remove the wheels and look from there. Need to check the differential anyway as I noticed a whine when accelerating and @jklett thinks it's low on fluid.View attachment 156187

Is this a Ford 9" diff?
View attachment 156188
Are there any "witness marks" anywhere that would indicate contact?
 

qclabrat

Well-Known Member
Are there any "witness marks" anywhere that would indicate contact?
There aren't, my good jack seems to need a service as there appears to be a leak, so stuck with using whimpy 2 ton version which can't get very high.
PXL_20210424_202703253.jpg

With the load off the springs, there thing seems tight.
PXL_20210424_190012847.jpgPXL_20210424_191354531.jpg

Reviewed the install manual for the rear and the seem to have welded the subframe to the right places as well with no signs of cracks or separation.
PXL_20210424_190111537.jpgPXL_20210424_191435077.jpg

Since the car was up decided to fill the differential, only needed about a 1/3 quart, but the pump was the way to go without having the car on a lift.
PXL_20210424_204759093.jpg

You were right about the use of delrin instead of rubber bushings. Many have commented on the "harsh" ride but that's the sacrifice for a stiff suspension I guess. Haven't gotten through to Speedtech yet, but hope to know more next week.
 

JerseyPete

Well-Known Member
There aren't, my good jack seems to need a service as there appears to be a leak, so stuck with using whimpy 2 ton version which can't get very high.
View attachment 156346

With the load off the springs, there thing seems tight.
View attachment 156347View attachment 156348

Reviewed the install manual for the rear and the seem to have welded the subframe to the right places as well with no signs of cracks or separation.
View attachment 156349View attachment 156350

Since the car was up decided to fill the differential, only needed about a 1/3 quart, but the pump was the way to go without having the car on a lift.
View attachment 156351

You were right about the use of delrin instead of rubber bushings. Many have commented on the "harsh" ride but that's the sacrifice for a stiff suspension I guess. Haven't gotten through to Speedtech yet, but hope to know more next week.
Is it possible that the springs are shifting position when under sudden load? There is no way to verify that without having to jack the car and suddenly let it down to see if it replicates it.
 
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