I have a 1997 LX450 with a bunch of mods and have been trying to hunt down a vibration issue that's eluded me so far.
To start with, the truck has both f/r axles rebuilt with new trunnion bearings, wheel bearings, 5.29 gears, Eaton e-lockers, seals, and RCV axles. The suspension has Delta radius arms, 6in Dobinsons IMS dampers, 3.5in dual rate Dobinsons springs, adjustable Dobinson arms, and steering stabilizer. Basically, the only thing that hasn't been changed on the axles is the steering arms, which are due soon-ish (the bushings look good, though). The drive shafts are Tattons. The brake calipers/rotors are new, front has Powerbrake 16in with a 4mm spacer (I cleaned/tightened this to be sure it wasn't the culprit). OEM wheels. All of the above with <3k miles. It has Slee sliders, which wrap the cats, 4x4 Labs rear and ARB front.
The issue is hard to track down b/c it's intermittent, but I'll be on a steep hill going to my house, get on the throttle, and at high RPM/load it'll start rattling/vibrating. It doesn't happen at high speeds, just below 30mph or so. The RPM isn't consistent. It happens often downshifting, but not always. Sometimes from a dead start on a hill, but never anywhere else. Doesn't happen as fast as I've driven the car which is about 75mph indicated. It doesn't happen when I manually select 1st or 2nd. Still happens with the OD off. Haven't tried with the other two trans buttons.
The drive shaft (which I had another thread about greasing due to me being a dumb dumb, sosry) U-joints seem fine, same with the splines. I pulled the front wheels and everything seems tight. I noted the RCV axles pull in/out a bit but there doesn't seem to be any other indication of slop anywhere. The exhaust seems tight with no loose hangars or anything like that, I couldn't rattle it by hand anyway. The swingout for the spare moves some but doesn't seem related based on feel. The motor/trans mounts look ok, no delamination or rot is visible. There is no noticeable change to steering. The trans fluid levels are fine and shifting seems to occur normally with no delay. It doesn't replicate when I two foot drive, either in 1/2 or D. The vibration can be felt slightly, but sounds worse than it feels, but it does seem to feel like it's coming from the driveline.
I've read through the other vibration threads, but none seemed to really align with the problems I'm having esp w/ so much having recently been replaced. Most work was done by the PO, so I have no idea if this existed prior to the axle/suspension work. I haven't had a chance to try in 4L to see if it replicates or pull shafts to drive in 2wd yet, but will try that this weekend, although the driveshafts seem ok unless it's a balance issue.
Any thoughts?
To start with, the truck has both f/r axles rebuilt with new trunnion bearings, wheel bearings, 5.29 gears, Eaton e-lockers, seals, and RCV axles. The suspension has Delta radius arms, 6in Dobinsons IMS dampers, 3.5in dual rate Dobinsons springs, adjustable Dobinson arms, and steering stabilizer. Basically, the only thing that hasn't been changed on the axles is the steering arms, which are due soon-ish (the bushings look good, though). The drive shafts are Tattons. The brake calipers/rotors are new, front has Powerbrake 16in with a 4mm spacer (I cleaned/tightened this to be sure it wasn't the culprit). OEM wheels. All of the above with <3k miles. It has Slee sliders, which wrap the cats, 4x4 Labs rear and ARB front.
The issue is hard to track down b/c it's intermittent, but I'll be on a steep hill going to my house, get on the throttle, and at high RPM/load it'll start rattling/vibrating. It doesn't happen at high speeds, just below 30mph or so. The RPM isn't consistent. It happens often downshifting, but not always. Sometimes from a dead start on a hill, but never anywhere else. Doesn't happen as fast as I've driven the car which is about 75mph indicated. It doesn't happen when I manually select 1st or 2nd. Still happens with the OD off. Haven't tried with the other two trans buttons.
The drive shaft (which I had another thread about greasing due to me being a dumb dumb, sosry) U-joints seem fine, same with the splines. I pulled the front wheels and everything seems tight. I noted the RCV axles pull in/out a bit but there doesn't seem to be any other indication of slop anywhere. The exhaust seems tight with no loose hangars or anything like that, I couldn't rattle it by hand anyway. The swingout for the spare moves some but doesn't seem related based on feel. The motor/trans mounts look ok, no delamination or rot is visible. There is no noticeable change to steering. The trans fluid levels are fine and shifting seems to occur normally with no delay. It doesn't replicate when I two foot drive, either in 1/2 or D. The vibration can be felt slightly, but sounds worse than it feels, but it does seem to feel like it's coming from the driveline.
I've read through the other vibration threads, but none seemed to really align with the problems I'm having esp w/ so much having recently been replaced. Most work was done by the PO, so I have no idea if this existed prior to the axle/suspension work. I haven't had a chance to try in 4L to see if it replicates or pull shafts to drive in 2wd yet, but will try that this weekend, although the driveshafts seem ok unless it's a balance issue.
Any thoughts?
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