Vibration under acceleration wont go away after new half shafts install
02-28-2018, 04:18 PM
#12
Yall may have missed that the holmes has a clutching LSD. Its chattering coming out of corners. Depending on the diff...this may be normal.
OP...are your two rear tires worn evenly? Air pressure good?
What type of diff? How aggressively is it set up? Is it in ok condition? Fluid ok? Proper fluid? Some take a very particular type of fluid....
Have you tried swapping in a known good OEM diff? Its easy....
The half shaft bolts have a torque spec. Don't go beyond that. If you feel like you over tightened the bolts by a lot previously...change them out with new OEM bolts.
OP...are your two rear tires worn evenly? Air pressure good?
What type of diff? How aggressively is it set up? Is it in ok condition? Fluid ok? Proper fluid? Some take a very particular type of fluid....
Have you tried swapping in a known good OEM diff? Its easy....
The half shaft bolts have a torque spec. Don't go beyond that. If you feel like you over tightened the bolts by a lot previously...change them out with new OEM bolts.
02-28-2018, 05:32 PM
#13
Yall may have missed that the holmes has a clutching LSD. Its chattering coming out of corners. Depending on the diff...this may be normal.
OP...are your two rear tires worn evenly? Air pressure good?
What type of diff? How aggressively is it set up? Is it in ok condition? Fluid ok? Proper fluid? Some take a very particular type of fluid....
Have you tried swapping in a known good OEM diff? Its easy....
The half shaft bolts have a torque spec. Don't go beyond that. If you feel like you over tightened the bolts by a lot previously...change them out with new OEM bolts.
OP...are your two rear tires worn evenly? Air pressure good?
What type of diff? How aggressively is it set up? Is it in ok condition? Fluid ok? Proper fluid? Some take a very particular type of fluid....
Have you tried swapping in a known good OEM diff? Its easy....
The half shaft bolts have a torque spec. Don't go beyond that. If you feel like you over tightened the bolts by a lot previously...change them out with new OEM bolts.
You are providing information that is a little convoluting to what i originally said...
I never said it was "chattering out of corners" that would make one assume that the clutch packs were making noise that is uncharacteristic in regular driving at speed out of corners.
I said the LSD was chattering in tight turns, pretty normal characteristic in low speed tight turns for a clutch type LSD without friction modifier or with the wrong type of diff fluid.
The diff oil is Amsoil 75W-90 Severe Gear with friction modifier now added. It has cut the chatter down in "tight turns" i.e. (below 20mph in parking lots).
This isn't a differential issue. Fluid is new, no metal flakes in previous drain, no issue with lock up, i do not drag launch my AP1.
The bolt thing though is something i will check next time it's in the air, thanks.
This is something wrong with rotational imbalance from either the crappy axles, or my propeller shaft (or both), my differential is fine I believe.
I possibly need a bearing and secondary shaft / bearing changed out in the transmission too.
Hell... It could be more than one issue TBH
02-28-2018, 06:54 PM
#14
You said the shake is more pronounced at 40+mph coming out of fast corners....if you're confident its not your diff, then...
Diff mounts in good shape? Maybe the torque is picking up one side of the diff because of a worn mount?
A bad bearing *may* cause shaking...but...it shouldn't become worse (or better) if you're coming out of corners.
Diff mounts in good shape? Maybe the torque is picking up one side of the diff because of a worn mount?
A bad bearing *may* cause shaking...but...it shouldn't become worse (or better) if you're coming out of corners.
02-28-2018, 08:11 PM
#16
Great, I’m trying to avoid spending 1900.00 on something that may or may not fix the issue. This is an ongoing investigation until I have a definitive answer that seems plausible or find something unusual when it’s in the shop on the lift. I just changed the axles (cv buckets included) AP1 has axle spacers installed from BLOX. I will check other avenues before I blindly drop $1,400 for another differential when my differential locks up like a dream. If it was the diff going it would have different characteristics than what is taking place.
03-01-2018, 03:05 PM
#17
Process of elimination
So in driving home last night on hwy 1 I was traveling the road at about 65 and 4000 rpm. I decided to try something different. I coasted the AP1 by depressing the clutch petal at 65 and yet keeping the engine speed up at 4500 rpm while coasting disconnected from the drive wheels. The vibration was still felt in my shifter just as pronounced as when it was in gear and moving the drive train. When the vehicle was coasting with the engine speed at idle there is no vibration.
The vibration I assume was felt before in the rear prominently because it was transferred from whatever was going on in the front of the AP1 while connected in gear.
This test has now eliminated any thought of the failure being anything mechanical further than the flywheel (which is lighted).
So my test last night eliminated the possibility of this problem being in the rear of the AP1 and it’s components like differential, axle, spacer, cv cups, propeller shaft/ or joint expiration.
So in my thoughts now, a cylinder is misfiring, coil has failed or secondary shaft or other unbalanced flywheel.
The vibration I assume was felt before in the rear prominently because it was transferred from whatever was going on in the front of the AP1 while connected in gear.
This test has now eliminated any thought of the failure being anything mechanical further than the flywheel (which is lighted).
So my test last night eliminated the possibility of this problem being in the rear of the AP1 and it’s components like differential, axle, spacer, cv cups, propeller shaft/ or joint expiration.
So in my thoughts now, a cylinder is misfiring, coil has failed or secondary shaft or other unbalanced flywheel.
Last edited by SennAP1; 03-01-2018 at 03:08 PM.
03-01-2018, 03:43 PM
#18
Whats the condition of your engine mounts? Any leaking? Inspect carefully.
If the engine is missing enough to cause vibration, it would be way down on power which would be noticeable, as well as triggering a CEL/misfire code assuming you are still running the stock ecu. Going to need more evidence the engine is the source. It could be in the transmission. Factory clutch and flywheel?
If the engine is missing enough to cause vibration, it would be way down on power which would be noticeable, as well as triggering a CEL/misfire code assuming you are still running the stock ecu. Going to need more evidence the engine is the source. It could be in the transmission. Factory clutch and flywheel?
03-01-2018, 03:59 PM
#19
Whats the condition of your engine mounts? Any leaking? Inspect carefully.
If the engine is missing enough to cause vibration, it would be way down on power which would be noticeable, as well as triggering a CEL/misfire code assuming you are still running the stock ecu. Going to need more evidence the engine is the source. It could be in the transmission. Factory clutch and flywheel?
If the engine is missing enough to cause vibration, it would be way down on power which would be noticeable, as well as triggering a CEL/misfire code assuming you are still running the stock ecu. Going to need more evidence the engine is the source. It could be in the transmission. Factory clutch and flywheel?