irvan

iTrader: (1)

My 89 IROC has a clunking, rubbing sound that has come back. I heard it once the day after I bought the car last November but it went away and now has done it 2 out of the last 4 times i've driven it. Very loud, sounds like the rear end is coming apart. Seems to be more on the left side rear and "feels" like something rubbing (driveshaft?) . I think maybe when automatic transmission shifts from low to 2nd. We put the car up in the air last week and checked the differential fluid level, the axles, brakes, u joints felt ok. Any ideas on what to look for or what next steps should be. Thanks

Drew

iTrader: (58)

Hows the transmission mount look? When they get really bad, it'll feel like a mule is under the car kicking you in your hip when the trans shifts hard into second.

irvan

iTrader: (1)

I didn't check that. I'm not sure i would know what to look for, thanks.

Drew

iTrader: (58)

When you look at the mount, you'll probably know. Or you can lift the trans a bit and if you see through the mount... LOL It's usually pretty obvious, but the weight of the trans can hold the two halves of the broken mount together. Very, very, very common in these cars because the torque arm is mounted to the trans, so they're under a lot of stress.

irvan

iTrader: (1)

Thanks Drew, I will see if we can get some time at a friends shop to put it on a lift this week.

JamesC

iTrader: (5)

While Pat is under the car, he might check the torque arm mount as well as the parking brake cables. I've seen this latter so loose that they can actually groove the drive shaft. If it's the trans mount, I'd avoid the OE Anchor version and go with beefier rubber:

Napa DTM 6441261/$19.79
O'Reilly PowerTorque A2672/$11.99
AutoZone Duralast A2672/$10.49 (In the note of this latter, it says "With Sport Shift—whatever that means)

JamesC

irvan

iTrader: (1)

Thanks James, now if I can just get him under the car.

JamesC

iTrader: (5)

Frankly, I'm surprised, ahem, that you yourself don't crawl under there. Shoot, I'd be ready with both my camera and EMT's on standby .

JamesC

blacksunshine'91

iTrader: (10)

When I looked that one up on AutoZone's website, it says that it does not fit my '92 T/A. But it does say it fits a '92 Camaro, although only the V6. Their website makes no sense sometimes. I thought the tranny mounts were pretty much all the same for automatics.

JamesC

iTrader: (5)

I note that both the Duralast 2672 and the Duralast 2394 will fit my car while only the latter will fit yours. If both will fit mine, I can't imagine why they won't fit yours. For more accurate info, you might check RockAuto.

BTW, Black, is there any chance that many years ago, I sold you an alum drive shaft?

JamesC

blacksunshine'91

iTrader: (10)

I don't trust the fitment option at face value at all. I just found it amusing that it said it didn't fit my car but it did 1990 through 1992 Camaros. The funny part was that the only year of Firebird it did say it fit was the 1993 year. Huh? OK.

Yes, I did buy an aluminum shaft off you....years ago. Like, YEARS ago. IIRC, it was probably around 2000 or 2001. Still on my '91 GTA all these years and two pinion yoke replacements later.

irvan

iTrader: (1)

One thing I forgot to mention is that the noise doesn't happen all the time, just sometimes.

JamesC

iTrader: (5)

At any speed or just when you "get on it" a bit?

JamesC

irvan

iTrader: (1)

Pretty much just normal acceleration, happens a couple or few times and then doesn't happen for a while.

JamesC

iTrader: (5)

Bumpy roads?

JamesC

irvan

iTrader: (1)

All kinds of roads but did notice once on bumpy stretch, happened the other day after leaving your house, happened leaving Slimmers Friday after getting the new starter installed. Probably try just showing up with the car and hope he can make time to look.

irvan

iTrader: (1)

Went to the shop and Pat drove the car (no lifts available), tried tight circles to check the limited slip, hard acceleration, normal acceleration, start and stop, thought he might induce my vertigo but no noise from the car or me. Guess have to wait for a time they can get it in and up in the air and hope Pat can find something his guy didn't.

irvan

iTrader: (1)

My apologies to James, I got under the car and crawled around checking stuff after you left, no cameras and no EMTs. Found nothing loose.

JamesC

iTrader: (5)

irvan

iTrader: (1)

nope, keep looking around under the car but not finding anything loose, need to get it on a lift.

NoEmissions84TA

iTrader: (1)

Whatever was making the noise probably fell off the car.
Problem solved.

irvan

iTrader: (1)

i would be thrilled if that were the case but i don't think that kind of noise.

irvan

iTrader: (1)

well, i stuck my phone under the car to take a picture since i could see some sort of fluid on the bottom and this is what i see. really like to get it on a lift so maybe i could tell what's leaking. I know, crappy photos that don't seem to tell me anything but general idea of something maybe?

NoEmissions84TA

iTrader: (1)

Now you have to use your 5 senses - stick a finger in it (TOUCH) and then LOOK at it, SMELL it, and maybe TASTE it.
I guess there is nothing to HEAR.

Unfortunately, I can't tell what it might be from those pics.

irvan

iTrader: (1)

yep, lousy pictures. My mechanic says he will have a lift free tomorrow so hope to get under it and look and feel and probably not taste but move stuff around and hope to find something loose.

irvan

iTrader: (1)

Put it on the lift this morning, looked around and we can't find anything obvious, transmission mount is good, nothing appears loose underneath. Pinion seal is leaking so needs replaced. Pat says next step is to pull cover off rear end and look (will replace seal then too) but he didn't have time today so I guess I still know nothing.

irvan

iTrader: (1)

Finally! Got it up on the lift and pulled the cover. Everything looks/feels ok, said clutches a little worn but normal/common. Pat made the decision to just change the fluid and add some posi lube and not replace the leaking seal until finding out if this solves the noise problem, i understand it was because he had other things he would rather be doing. Lucky for me I was able to arrange a technical advisor to stop by. James C couldn't stay away from the bottom side of a third gen. All back together and I guess see if the fluids solve the problem.

JamesC

iTrader: (5)

Glad to see you photographed my best side Were you surprised at the gearing?

JamesC

irvan

iTrader: (1)

I was, 2:73 seems strange for an IROC.