I'm at the end of my rope. Mama's 2002 tacoma, 3.4 4x4 auto. Just hit 200k. Intermittently, only under throttle, the truck makes a noticeable moaning/groaning noise. Its not bogging, and I cannot recreate the noise in park, only while moving, again, under throttle. If I let off the throttle it stops. I've done the following: fuel filter, timing belt, water pump, cam and crank seals, plugs, wires, cleaned the maf, new cats, new brakes all around including rotors and drums, changed both diffs and transfer oil, and swapped out a slightly binding cv. 2 months ago I installed a custom rear drives haft with Spicer u joints and a new support bearing. Sometimes it also makes a chirping noise, I thought bearings but during the brake job I spun each wheel numerous times and can detect nothing. Checked if they were loose, they're not. Could the groan/moan under load be a bearing? I thought maybe it could be fuel related but again, it doesn't bog again all. Thanks for reading I'm losing my sanity.
