How many miles and year of Supra?
A loose top strut nut or bolts is a near constant rattle.
Might also be the steering rack bushing.
That makes a clunking sound. To test, turn your steering wheel left and right. If you hear the same noise the rack bushing.
The fix? Grease.
What state are you in?
If the Supra is your daily and you live in an emissions state, maybe consider the stock cat because it is designed to last longer (10 years). No sense in buying another aftermarket cat that may fail emissions in 4 or 5 years.
FWIW, somewhat similar dilemma. Previous owner let the alignment go and chewed up the front tires. I ordered a *used* set off Pilots off ebay, about $480 for a set of 2 with 8/32 tread depth and installed locally - warranty included. OEM sensor or aftermarket (Gorilla), they both worked for me...
OK guys, I am going to bump this thread.
BIG thanks for @RAWSupra for chasing this down.
My 2022 3.0 Premium US Spec Supra had 25,000 miles. The last 6 months I have been chasing a knocking sound. Low speed, rough roads, coming to a stop, and turning the steering wheel left and right... clunk...
The M2, great interior and drivetrain... design of the body? Autobot inspired by Temu.
Personally, M3 or M4 if you need the room. Which I get as a GenX dad. I would have been a 25+ year Mazda Rx-7 club member if the RX7 had a back seat. So in 2000 I got an E36 M3 and owned BMW variants since...
Check your spark plug wires/coils. I replaced my plugs on my 435i and didnt fully seat the spark coils. The drive train error blipped as soon as I started the car. Easy to check especially if you pulled them off recently.
Learning something new everyday... the 2.0 Supra got the AUX battery. The 3.0s do not.
"On the 2.0L Toyota GR Supra, the auxiliary (second) battery is located on the passenger side, under a black cover/cowl in the engine bay. It is used for the start-stop system and is not found on the 3.0L...
Ok learned something new, ran this through AI...
Check the battery!
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While AGM batteries are "sealed," they are actually VRLA (Valve-Regulated Lead-Acid) batteries, meaning they have a safety pressure-relief valve designed to release gas if internal pressure gets too high. [1, 2, 3]
Why...
So less power, no slip.
Generally when you bump the HP significantly, most people upgrade the clutch plate and disc. The pressure plate to keep well pressure on the disc/flywheel and the disc to grip the flywheel surface.
LOL, gentlemen... BOLDED the portion of my comment where I mentioned adding oil to bring it to maximum fill.
For a daily driver, oil starvation (like the old S52 and S54 BMW motors under track conditions) is not a thing.
So overfilling by a 1 liter or a quart isn't necessary.
I think you overfilled the oil.
So in my experience you don't dump all 6.5 liters/6.9 quarts into the engine after an oil change. That is the capacity. Nearly 1 liter/1 quart can sit in all the oil passages and lines. So it's easy to overfill the oil. Too much oil and you can quite literally...
Can you take a photo from the front of the car showing the difference? If the Supra is like any other BMW, there is a decent amount of adjustment to get panels aligned right.
I say this because on my old 435i and M3, I sometimes needed a floor jack under the front nose cone to hold it in place...
Alignment. Agreed.
The car's stock alignment will send the rear end sideways. Dangerous given this "is your first sports car." I kicked out the rear end of the Supra in a light rain... on the test drive... at 35mph. Now this was punching the throttle, so the rear will wiggle SOME. But sideways...