Its been a bad year for cars for me. Had a driver fall asleep at the wheel, up my driveway at 100mph, and took out 3 cars: 07 Mustang, 96 3000GT, and an 82 280ZX. Replaced two of the cars with an 02 T-Bird (should be the problem car, but its actually been solid - just putting more miles on it than I wanted to because of the following), and an 05 Mustang GT that was supposed to be the daily driver, but has spent so much time in the shop this year I've barely put 3000 miles on it. So far have replaced the soft top, top motor, half the interior, the entire suspension, wheels, tires, half the cooling system, and all the below. So now I'm upside down in it, and while I should be driving it (and will need to for a couple of years to break even again), I'm still having the following two issues still and it keeps just going back in the shop.

05 Mustang (130.000 automatic 3.6l 3v) that I've done everything to, with two different shops that are now just pointing fingers at each other, and still have two problems that I cant get solved.

1. Vibration at 65-72Mph - I have replaced every piece of the suspension front and rear, motor and transmission mounts, every bushing, wheels and tires twice, hunter road balance, transmission fluid change (car threw a code at one point on fluid pressure), literally everything except the rack and pinion (which both shops agree on is fine), and I still get a minor vibration that changes from the floor to the steering wheel at these speeds, more pronounced in warm weather. Goes away above 75 and is smooth as glass. One shop is telling me to get the driveshaft balanced, or its the harmonizer. Second shop (a Ford specialty shop) is telling me it cant be either of these. I have had to fight between both shops finger pointing at what one did suspension wise and what the other did so far. (as an example, shop1 told me a noise in the front was not the sway bar bushings, had shop2 change the bushings and sound went away. Conversely, shop2 told me my rear suspension was fine, shop1 told me rear control arms needed to be replaced. After replacement, I definitely noticed a difference, rear had been "wheel hopping" and focusing on the front issue I never really noticed it before - then 2nd shop tells me again that suspension was fine, they drove it as well as inspected, and I just got ripped off on something I didn't need).

2. The main problem - in Dec, I had the car run hot. Took it to 1st shop they replaced thermostat and changed fluids. It ran hot again a week later, took it to 2nd shop (a Ford specialty shop), they determined I had the relay issue that is common in these cars, and ran a custom wiring with 30amp relays. Ran fine for about a month, then ran hot again. Since I was already planning on having 2nd shop do the timing chain guides/chains, I took it there again. They did the chains, the top end (valve guide seals, gaskets), the thermostat (again), the internal engine cooling lines, a recommended CVT lockout, and with that a custom SCT tune. Add to this the PCM started throwing ROM codes just before I took it in, so also a remanufactured PCM (they wanted one from Ford, but with pandemic Ford still does not have them in stock - went with a reman from a reputable shop). Also determined the relays they had put in burnt out and the 2nd overheat was the fans not turning on, so they upped to 75amp relays, and a 30amp fuse package to protect it.

Had the car back two weeks, and the overheat happened again - had it towed back to 2nd shop. They are now saying that either the tune is not kicking the fans on at the lower temp that they had told SCT to put in the program, or the reman PCM is bad. I am more leaning towards a weak radiator or intermittent issues with the fan clutch switch. Car has been sitting with them for 3 weeks with no solid answer. They are currently waiting on SCT to modify the tune before looking any further. They say though that the fans are operational, just once in their 10 or so tests it "didnt come on as early as they want it to", but even then it never overheated on them.

The only thing I can add as an operator, as odd as this might sound, both times it ran hot towards overheating the weather here in Fl happened to be not only very hot (97+), but both times we had that "pea soup" stagnant humidity that comes just before a major front drops tons of rain. The other thing that was interesting in both cases was the temp gauge would be slowly going up at stoplight, but would go up quicker when I accelerated out of the stop. Which normally would make me think weak water pump or system has an air pocket - shop2 is adamant that neither of these are the case.

Car has not set any codes or shows any history even showing it had run hot, or went into limp mode (although I felt the engine go into "limp mode" to try and cool itself off at idle when this happened) shop says it may be because I was too quick to kick the heater on to aid the cooling (too old-school as an operator - if its running hot, get the heat out asap, so I'm quick on the kill the AC and turn the heater on!), and of course they are also blaming it on a possible PCM issue with the remanufactured unit. Although I still find this hard to believe - I feel like they are pointing at this because they couldn't get the part from Ford and "do not trust other remans". (This shop is not a dealership, but is hardcore "Motocraft supplied parts or die" - they even keep telling me the problem with the suspension issue above is because Shop1 used Monroe shocks instead of Motocraft - I find that hard to believe based on my issues with the arguments about the sway bar bushings, the rear control arms, etc - it seems my gut on what's really wrong has been the correct one even when both shops are telling me I am wrong and its something the other shop did or didn't do, yet when I tell one or the other to go ahead with my gut instinct, the problem I complain about goes away every time).

Can you offer any advice on either of these issues, or even an opinion if I am being fed a line of bull? Every time I leave one shop or the other, I am out another huge chunk of change.

Here's the kicker - I trust both shops. Or at least I should. The 1st shop I have done business with for 10 years and they have never steered me wrong, but they are mainly a tire shop (chain store), the 2nd while this is the first I have used them is a small shop, specializes in Ford cars, and is highly rated in the area, and has been around for more than 25 years. But the finger pointing with no solutions is driving me crazy - as well as the car being in one shop or the other for the better part of a year.

Sorry about the long read, but thanks for your time. Ive been watching your videos for years, and I trust your opinion.