Good info to narrow it down. What if the vibration in my wheels is RPM related BUT vibration is only in the steering wheel? Car still rides smooth its just the steering wheel that has feedback.
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Good info to narrow it down. What if the vibration in my wheels is RPM related BUT vibration is only in the steering wheel? Car still rides smooth its just the steering wheel that has feedback.
vehicle issues are structural, mechanical, or electrical. i aint no mechanic, this is the system I use to narrow it down. Structural is something bent (like an axle or frame or driveshaft or lower control arm or bent rim or warped rotor), misaligned (like a driveshaft or the caster-camber-toe or front axel after a collision), or broken (like a rusted end link which finally breaks in two or a busted motor or transmission mount). Mechanical is moving parts, all the kinetic stuff (like u-joints and camshafts and cv joints and fan clutches and water pumps and innards of an automatic transmission and pistons and brakes and bearings, stuff that moves and breaks and wears out). Electrical is electrical (fuses and wires and relays and switches and computer boards etc).
What structural deficit could lead to this vibration?
What mechanical failing could lead to this vibration?
What electrical failure could cause this vibration?
Could it be some combination of these?
"vibration in my wheels is RPM related BUT vibration is only in the steering wheel? Car still rides smooth its just the steering wheel that has feedback."
RPM is how many revolutions the engine,crankshaft and transmission/gears are turning and is independent of speed. These components can turn at 3000 RPMs at a variety of speeds.The driveshaft and axle RPMs directly correlate to MPH/wheel speed and are not RPM dependent.
Wheel, rotor, pads, bearing, axle, cv joint, front differential, front drive shaft, transfer case, rear driveshaft, u joints, slip yokes. I don't think any of these are RPM dependent.
So what connects the steering wheel to these RPM components? Steering wheel, slip joint, steering rack, inner and outer tie rods, upper/lower ball joints, control arms are not involved in the RPM thing. So the vibration is being caused by other components which lead to the wheel OR the vibration originates from a component that is close to steering components or from a component failure which is allowing direct (metal to metal) contact by two parts that would normally not touch, i.e, worn motor mount which no longer isolates engine movement/vibration from rest of vehicle, so the vibration is transmitted through the steering system due to proximity. Just because you feel it through the steering wheel does not mean it is coming from the steering or suspension system. I mean, it is RPM dependent and therefore HAS to originate from the engine/transmission, right?
"drivie" speaks about "turning on a curve in the freeway, I can drive into and out of the vibration multiple times while maintaining the same speed and it comes and goes more quickly." perhaps the engine shifts a bit to the side and is held fast by the centrifugal force generated in the turn. As he "drives into and out of the turn" the engine is being held fast then not, held fast then not, etc. When driving straight it is loose and and saggy and moving around without the benefit of good motor mounts. The bad mount allows it to move move side to side and front to back and up and down, and the degraded rubber no longer buffers the rest of the truck from the engine. Motor mounts can fail in different ways so you may not have the same result if you try driving "into and out of the vibration".
If you can replicate the vibration while truck is stationary see if there is some way to secure the engine so it doesn't wobble so much. Maybe a long pry bar and a couple of short 2x4s against which to lever so you don't dent the engine compartment or damage the engine. Stick that pry bar in there, apply force, and see if the vibration goes away or changes intensity.
Have you had a friend run the RPMs up while you look and touch and listen to the engine (be SO CAREFUL to not get whacked by the FAN BLADE. It will CHOP off your finger or put a deep nasty ER-visit-gash in your arm. It is so easy to forgot for a few seconds and suddenly, whack! ouch! ick! I feel woozy). Get under the truck while your bud does this. Don't burn your face or hands on the hot hot muffler and catalytic converter. Listen really carefully for a long time. Keep looking looking looking and listening. You should be able to localize it. If you cannot replicate the vibration with the vehicle standing still you can focus on the drivetrain, all the stuff that is driven by the engine and changes RPMs as the engine does. Perhaps it is coming to you through the steering wheel because that is your most direct tactile connection to the goings on up front.
RPM = frequency. Maybe a failed motor mount manifests its damage within a certain frequency range. These are rubber components which absord an enormous amount of energy and eventually fail. Even if they don't actually tear/split the rubber degrades and compresses, allowing large components like engines and transmissions to sag and shift. And a degraded mount would allow greater movement of the engine/tranny/etc/whichever than it is designed to accommodate. If the things that hold a thing in place lose their structural integrity, then the thing being held will no longer be where it is supposed to be.
1) Structural. Mechanical. Electrical.
2) friend run truck in RPM zone while you look and listen.
3) pry bar to secure engine
4) motor/tranny mount.
Or not, I am just speculating. This is the thought process I go through when trying to figure out what the f*** is wrong with my f****** truck...
