Corvair Forum

Hello, I have a 1965 corvair. Rides smooth and quiet until about 50 mph then is noisy and buzzy. Thought it was rear wheel bearing, but took wheels off and seems tight and smooth. Noisy definitely comes from rear. Any thoughts?

Is it a posi?

Jasonsmith wrote: ↑Wed Apr 23, 2025 5:32 pm Hello, I have a 1965 corvair. Rides smooth and quiet until about 50 mph then is noisy and buzzy. Thought it was rear wheel bearing, but took wheels off and seems tight and smooth. Noisy definitely comes from rear. Any thoughts?

Your explanation is too general, not even a statement of about PG or manual. Your problem could be so many things it is impossible to narrow it down.

The last time somebody asked about "noise" at speed, I said "Did you check your transaxle lubrication level?" They found there was little lubrication in it and it was RUINED.

I suggest you find a Corvair repair person to check it out.

I agree, a better description of the problem. At 50 and above, a posi shouldn’t make a difference. Main noise issues there would be cornering. I also agree, start by checking your differential fluid. Your 65 should have a dipstick on the right front corner of the engine bay (two if it’s automatic). Start with that and as good a description as you can plus automatic or manual transmission.
I see you’re new, welcome if you’re not a bot.

Sorry. I am new to the corvair world. Different than I'm used to working on. That said, it is a 3 speed manual. I have checked transaxle fluid , it is full. Just trying to narrow down possibilities. Thought I would ask people with more knowledge. Thank you.

Jason,
Maybe on a safe stretch get it up to 60 and shift into neutral and observe any changes.
Also check heater hose above drivers side axle and make sure it’s not rubbing.
Good luck
Will
69 500

Well, you came to the right place!

Have a mechanic's stethoscope to hold on the rear axle bearing assembly while you spin the rear axles? If no sound while spinning them with your hand, spin them in gear while the car is up on jackstands or wooden blocks. Safety first!

Jasonsmith wrote: ↑Thu Apr 24, 2025 6:09 pm Sorry. I am new to the corvair world. Different than I'm used to working on. That said, it is a 3 speed manual. I have checked transaxle fluid , it is full. Just trying to narrow down possibilities. Thought I would ask people with more knowledge. Thank you.

No problem, we all started out knowing little about cars.

Not sure if this is your first "old car". Did this noisy problem just happen? If not it may be that you are not used to the higher RPM old cars run at on the highway. Modern cars use "overdrive" to reduce drivetrain noise (and better fuel mileage) on the highway. That said - see if you can find a local club and someone who can go for a ride to listen.

Ok, ok, I currently own a 1968 cutlass, 1963 rambler ambassador , and 2016 challenger scat pack. I'm very knowledgeable about older cars. Work on family cars which include 1957 chevy, 1972 buick skylark and 1987 corvette. That said, none of these are rear engine air cooled cars. Moved outside the box and want to learn more bout this strange little car. I purchased it recently and test drove around town before buying. Once purchased I drove home around 40 miles after it had been in dry storage for many years. Anything above 50mph the noise is drowning. Not sure if it the nature of these cars? I jacked up rear and placed on stands today. On drivers side if I put hands at 12 and 6 the tire rocks up and down. My guess wheel bearing. Th a nks again for any info.

That up and down motion of the rear wheel is probably normal. Watch to see if the drive shaft is moving in and out. Some have quite a bit of motion. Some came like that when new and it doesn't seem to hurt anything. If a wheel bearing was bad you would have motion all of the way around at any position. A drowning sound can come from the exhaust?

Droning exhaust can be prominent expecially with a non factory exhaust. Exhaust system can drone (vibratory harmonics) from loose baffles in mufflers, loose hangers, worn out donuts both at the manifold to u pipe and at the cylinder downpipes and manifold, etc. Make sure your exhaust is tight and doesn't impinge on body sheetmetal or engine shrouds.

More troubleshooting for you. In addition to previous suggestions

If you have a tach, note the engine RPM's range at 50-60 during worst of droning in 3rd gear. At next light, when accelerating see if in 1st or 2nd you get droning at the same RPM range. If so most likely exhaust noise (especially with trombone system or non stock exhaust). Also get up to spd and put in Neutral and see if noise changes(this changes loading on the pinion and ring gears.) Does the noise change, increase or decrease in gear while decelerating? Does frequency change (High pitch at speed to low pitch as you slow down). Is the noise constant or does it have a frequency to it (about once a revolution to the wheel)?

If the noise is strictly speed dependent, then wheel bearings, "U"Joints, diff bearings. If the noise is on the left side does it get worse if you load the bearing sideways (right hand curve), if so most likely outer wheel bearing. Conversely turning left curve and the right side gets noisier, the Right bearing is culprit.

How far does the left wheel go up and down or is your movement in and out (top out-bottom in then reverse direction).

As for noise, Air cooled are always noisier than a comparable water cooled engine (put it next to a Subaru for comparison). And there are literally little to no factory noise reduction measures taken with regard to the Corvair.

My '64 had trombone exhaust with the balogna cut pipes on it when I bought it. Idle was fairly quiet but get on it even a little and it sounded like a P&W R-2800 from a Corsair with short stacks at 25ft running wide open, go full throttle and it got very harsh and louder like a R-3350 972-TC-18DA-1 Turbo-compound engine from a Constellation. It got old real fast, to the point where I had to remove my hearing aids just to hear myself think. And boy did it DRONE between 40 and 50. And it wasn't all noise. There was a frequency harmonic that caused the car to act like the inside of a tympani. Between all the DURAMAT on floor, back shelf, insides of doors, and the quarter window panels, it's relatively quiet now. It still sounds like a EM with a 140/PG but it's somewhat muted but normal sounding with my hearing aids in. Wife liked the look of the dual pipes out the back, but 1 ride around the block and she told me "GET A NEW QUIET EXHAUST, I'll PAY FOR IT!" I put Clarks factory duals on it for a 140. Compared to your Rambler, Olds, Buick, possibly the 57' or the vette, it's a threshing machine. It's got it's own sound and thats part of the allure. Like the old VW Bug, you can identify it just by listening to the exhaust and engine noise as it goes by (even if you can't see it).


Hope the problem is simple and easy to fix.

Wow! Mention of a "Compound 3350". Someone else speake my language (although I'm partial to Allison V-1710s). I don't get arounf warbirds near as much as I used to.