Forgive my bluntness but unless you grab this bull by the horns, you are going to continue to risk getting gored. As 67:72 said, part of owning vintage Corvettes is having an awareness of what makes them tick (and quit ticking occasionally). If you don’t embrace that, then you would be better off buying something a lot newer.

What does “It’s really not that bad” mean? Does he have any idea of where the alignment is? Did he explain to you what specific defect in the trailing arms does he believe is causing the wander? Loose/worn bushings where the arm meets the frame? Loose/worn strut bushings? Loose wheel bearings? Worn stub axles (inside the differential)? Loose/worn u-joints?

If the front A arms, in his opinion, are “worth rebuilding”, why is he focusing on the trailing arms?

”Resealing” the diff is a lot different workscope than rebuilding. How many C3 differentials has he rebuilt? I think I asked you in your previous post how bad was the leak in the diff. If it doesn’t create a puddle underneath the car, it is something you could live with. If he doesn’t know his way around these differentials, you could end up with more headaches down the road. If it ain’t broke, don’t fix it.

Unless you are planning on stuffing some monster tires on 12” rims, you don’t need offset arms. I have a 69 running 28x12 Mickey Thompson’s on 15 x 10 wheels with my original stock arms with no issues. Keep in mind that your trailing arms likely have the original axles and rotors. Unless you send your own arms to a rebuilder like VS, you may end up with cheap imported parts on an exchange.

As I posted earlier, get the alignment checked. Inexpensive, quick, and will either eliminate a lot of guesswork or or correct your wander.

As for the fuel leak, is the problem a rusted tank? If yes, order a replacement from Quanta. The tank is $245 and the straps $52. Be sure to order a sending unit o-ring and retaining cam and rubber connector hoses and clamps. Whoever replaces the tank needs to be Uber careful when removing the sending unit as OEM quality units are no longer available. If you do change the tank, be sure to recover the tank sticker (on top of the tank if it is still there). This is worth something as it reflects the original build specs. Ratty as it may be, keep the sticker!

 

The new guy gave you the advice I was about to give. Much of the wandering is in the trailing arm bushings, and likely the strut rods as well (you can get a huge improvement by going to heim-joints, or just rebuilding what you have). If the control arm bushings are okay, a proper alignment might solve the front of the car.

You don't need new trailing arms, unless you want to put really big rear wheels on the car. I did my rear hub bearings at the same time, so I sent both arms out to be rebuilt (not replaced).

Did you get a quote for all of that? The throw-away "I'll do the diff while I'm in there" comment makes me think this will be expensive, but at least it sounds like the new guy might know what he's doing.

 

I appreciate everyone's input to be sure. And I'm sure I'll learn a few things along the way. But to be blunt right back. Not everyone has the time or aptitude to learn all this stuff but still deserve to drive the car they want. Don't you think?
I work 55+ hours per week, and still have a 7 year old at home. My life is very full and spending all my evenings in my garage would make my son sad, and my wife mad.

No, he didn't explain, and I didn't ask. This was a fairly informal high level look. When we drove it down the road he weaved back and forth pretty hard a few times to get a feel for the car and said, "It's not that bad".

He looked at the fronts and said the bushings were still there but old, so I could live with them as is, or rebuild them. The major factor in the wander in his opinion was the trailing arms, thus, his focus was on them first.

He said the whine I hear is from the diff, could just be bad/low fluid. Might need to be rebuilt. He's been in business 30 years and had a shop full of vettes and a few Mustangs. Several members of a FB group for Florida corvette owners recommended him.

Good to know, not stuffing monsters on there so I'll stick with regular ones. I was planning to buy these. Do you suggest something else? Remember, I don't have space to keep the car in a torn apart condition for any length of time. Can't ask the shop to take up a stall while parts are sent away to be rebuilt.
http://www.vansteel.com/index.cfm?fu...p=3000&ID=1835 <-- obviously one for each side.

I've seen enough of the mechanics rock my tires to know an alignment check would do no good as the tires themselves rock back and forth. Alignment and new tires come after they'll stay put.

Thanks for the info, will pass it along.

 

No quote, and he didn't say it in a manner that made me think he'd just do stuff without asking first.
He flat out said I won't do anything you don't need. And he also said that once it's up he'd show me everything under the car he believes needs to be done before starting any work (aside from the already agreed upon items that have bene previously discussed).
I think he more meant that if the diff needs to be done, best to do it while doing the rest of the work back there, not that he'd do it no matter what to pad his wallet.
I showed him a copy of my other estimate and he said it was crazy, he'd never charge those kinds of prices for parts. "I'd be out of business if I charged like that."

 

As you can tell from our collective posts, none of us want to see anyone being taken advantage of as we all know the propensity of certain folk thinking like Phineas Taylor Barnum, especially when a sports car is involved. We post in this forum because we want to help but if advice is being discounted then it becomes problematic for us. In fact, this post is titled “Replace Control Arms” but has digressed into offset trailing arm questions.

You say that you’ve seen enough mechanics rock your tires to know that an alignment check would do no good. Yet, your latest guy says “it’s not that bad” (the “wandering”) and that you can live with your A arms as-is and says your trailing arms are the problem but can’t/won’t identify what specifically is the reason. What am I missing here?

If your front tires “rock”, it’s either worn ball joints, loose wheel bearings, and/or deteriorated control arm bushings. I’d recommend you address those issues first as they are the least costly/least complicated.

Finally, at the end of the day, your family is infinitely more important than that car. My 69 sat for 30 years while I prioritized my family.

 

Click on the link in post 16. Look at the pictures.
https://xoxocar.com/inspection/17237...56f6ba8?sb=def
I think we can all agree that the quote is laughable (also in Post 16), but the problems they identified are real.

Ball joints, wheel bearing regrease and adjust, rebuild rear trailing arms including bearings and trailing arm bushings. Replace or rebuild "camber arms" (strut rods). And the fuel leak, and brake fluid leak. Those are the real priorities I see (but please form your own opinion).

A lot is easy stuff, like the sway bar bushings. But it adds up.

That's at least $1500- worth of stuff if you do it yourself. Farmed out, $3K? $5K? $More?

 

I've been thinking about your car and the need (at this point) to have someone else do the work. I looked at all of the photos that Rich's (btw, their acronym is "RATS" ) took of the car on the lift. I firmly believe most of the stuff is on the long-term repair needs list and has no immediacy to get it done before driving the car. The two exceptions are the gas tank issue and the issue causing the road wander. Once on the lift with the mufflers removed, it's not unreasonable to do both at the same time. All of the various lubricant leaks and drips are not safety issues, merely annoying.

Here is what I would do: order two rebuilt trailing arms (I prefer stock replacements but that's up to you), a Quanta gas tank, two straps, and a filler neck gasket. If you feel flush, you could also replace the sending unit since it's a bugger to replace later if needed and they do wear out. If the sending unit doesn't come with 0-ring seal for the lock ring and a "sock" filter for the end of the pick up tube buy those too for good measure. Since you're putting in rebuilt trailing arms with new bushings, bearings, seals, etc, it makes sense to also replace the software (see what I did there?) for the connecting components so... I'd also order the various rubber bushings for the spring bolts, strut rods, and sway bar ends. Other than the trailing arms and gas tank, I'd try ordering as many of the other parts from my local NAPA or O'Reilly's as I could. They aren't that specialized and it makes it a lot easier to exchange or return if needed.

As for the differential, at this point, I'd only replace the oil and add two bottles of positraction slip additive to see if that quiets the whine. To properly address the differential is to remove the spring, drive shaft, half-shafts, and lower the unit from the chassis. The characteristics of what the car feels like to drive don't indicate to me that the differential internals are worn or damaged, so, I think it's warranted to just try the fluid change. (I use GM Delco branded over-the-counter oil and additive from my local dealer.)

Prior to this work being done you could also see if you can get the entire underside steam cleaned. This will remove the various spots of excess oil and grease so you can begin fresh isolating what and where the attention should go next. It's also nicer to work on a clean-ish underside than one coated with gunk.

 

Thanks for the additional info. I've got replacement trailing arms and control arms on order from VanSteel. $250 to ship across the state so I'm going to drive over and pick them up. It'll be a nice day trip.
The mechanic I decided on is charging $350 per side to do the TAs, I don't think that's too outrageous based on everything else I've seen.
Stan (the mechanic) said he'd look at the diff and only rebuild it if it was needed. He actually told me that he's seen them make crazy noises just from having the wrong type of fluid in them and that would be the first thing he would check anyway.
He mentioned that a new fuel tank should only be about $200 or so, makes me think he's on the right wavelength to work on my car.

Once my suspension parts are ready for pickup I'll see if he's willing to take the old parts off first so I can make just one trip to VanSteel and drop off my cores when I pick up my new parts. Would be nice to have those core charges back quickly ($1000 total).

 

Sounds like a good plan and Stan seems to be telling you good info -- the differentials need specific gear oil and must have the correct additive. I think a lot of folks think the additive is merely an STP snake-oil type thing but it's a GM design spec lubricant that must be used.

A road trip sounds nice and shipping is a killer on these types of things. I ordered a set of seat foam and the standard shipping across multiple vendors was $100. Thankfully the vendor I used was offering free shipping at the time.

BTW, I hope you picked up on my suggestion to order two tank straps. The one broke for a reason and the other likely has the same condition plus the added stress of securing the tank since the first broke.

Please do keep us informed as to how the rear end work goes and how Stan is to work with.