Loud “Clunk” in Fourth Gear…Tranny?

[OK-944]

Less than one half mile from home, gliding gently down a shallow, smooth slope in fourth gear - almost no pressure on the throttle when…CLUNK!! Pretty loud and “percussive.” Could really feel it. Might’ve hit something, but sounded/felt worse.

So I pressed in clutch, shifted to neutral, and stopped the car. No flat tires…no sounds from suspension when pushing down at corners.

Drove back home but did not go above third gear. Engine is fine…good oil pressure, sounds, etc.

While its possible that I just hit something - like a large stick which flew up into my wheel well…I’m thinking that I should at least test the drivetrain, and need to pick some brains about this.

I’m thinking that the least “invasive” way to check the tranny would be to lift the car, put it in fourth gear, and turn the engine by hand, with the front crank bolt, to see what happens.

Alternately, I could start the engine with the car lifted, and let the engine idle while I slip through the gears…perhaps starting with second so as not to shake things up with the car lifted.

Or…I could just lift the rear of the car on jacks, chock the front wheels, and do the “shifting while engine runs” test.

Question: if I do the tranny test with the engine running - might I put less stress on the CV joints if I at least removed the rear wheels/tires? Or is it OK to let the wheels/tires hang and spin while testing?

Another concern is that the tranny might have thrown a tooth, which might cause further harm. This possibility is what leads me to thinking about spinning the engine by hand as mentioned above.

At any rate…any comments would be great. Thanks!

[mytrplseven]

Whatever has happened, It's already done. Raise the car and look at the obvious: loose bolts on the drive cv's, oil leaking, loose shocks, missing bolts on wheels, sway bars, Transaxle mount. Then I'd raise the rear or the whole car and put the car (with engine running in idle) through the gears and listen for abnormal noise. If nothing, raise the RPM to see what you have. Good luck.

[944 Ecology]

If the transaxle "threw a tooth", running it in gear, on the road for a couple of hundred yards is not going to do much more damage. I say take it for a short test drive and feather it in fourth and see if there is any more noise. If not, drive in peace.

[OK-944]

Another possible culprit...the drivers side ball joint seemed a bit stiff when I'd earlier re-installed that control arm. I had also removed the joint's boot (not cracked but a bit worn), re-lubed the joint as best I could, and installed a new boot.

At any rate, awhile ago, after the car had sat for ten days while I was away, I drove the car into town, then I heard/felt a "clunk" (not nearly as noisy as yesterday's) coming from the direction of that ball joint...as I backed the car out of a parking space.

My thought now is that this ball joint is finally binding badly enough that it holds a position until the car puts enough pressure on it to break it free. Indeed, I'd been turning into a right sweeper when this most recent "clunk" happened.

So...fingers crossed that its the ball joint - and that, if so, it is still replaceable - and that there is no further damage to any associated/adjacent parts.

[Fast Freddy 944]

Clunk could be cv's going out, ball joints, or something loosened up. Lift it and check it..

[OK-944]

Got the car up this morning...poked, prodded, levered stuff around, lifted wheels individually (with a hand grasping ball joints to verify movement) - and all looks well. Took it out for a ride...and...all is well! Great actually, after draining the final fill of break in oil and replacing this with 10/40 - pulls amazingly well and smoooooth!

So....I'll assume for the time being that I hit something.

Right now...I've gotta get back to it - Just received some great looking fuel hoses from Len Cummings, and will now install those. After this...I take a true leap of faith - and start looking at snow tires! There's simply no way...after my car's eighteen months on the lift for the rebuild/rehab, followed by another six months of on again, off again, hair pulling/head-scratching "dialing in," that I'm going to just put it back on the lift to let it sit through the winter...no friggin way!

[walfreyydo]

I think more investigation is needed as Fast Freddy mentioned. Lots of possibilities, I wouldn't rush to assume its your transmission until every possible other option has been eliminated.

PS: Please dont drive your car in the snow! Even with galvanized bodies, the salt will turn everything thats not galvanized rusty, including all that fresh new hardware on your rebuilt engine. Of course the choice is yours but I always cringe thinking of these rare and beautiful cars being driven in salt! I live in Wisconsin and I understand the torture of not being able to drive my car for 4 months out of the year, but I thank myself whenever I look under the car and see how clean and restored everything looks (and stays that way). Considering all the pain and suffering of rusted bolts, hardware being replaced with new hardware, wire wheel/sand blasting and painting parts, I never want to go back to that!