Clunk when braking (not rear diff clunk) - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

dfwRobert · 08-23-2018, 02:17 PM

I have a clunking when braking mostly but also when accelerating. It is NOT diff clunk. Let me say I have had a full Prothane bushing kit out back including the diff bushings for over 2 years now. I hear diff clunk like a mofo all the time daily. I know THAT sound. This is different.

This sound happens if you are slowing down from 20 plus and brake med to hard but not super hard. You hear one single thunk. It sounds like it is under the shifter. You can feel it in the shifter also if you keep your hand on it. To make the noise again I have to first take off kind of med to hard acceleration. If I was to baby the car from 0 out to 30 or 40 and try again I don't think it would happen. So in other words if I was going 40, hit the brakes hard then let off and tried to brake hard again it would not do it a second time.

When I accelerate it will make a much softer thunk or clunk that is much harder to hear/feel. It is as if something is moving back and forth in the trans tunnel. Also it seems 2nd feels kinda weird at times. Like I have to pull into second and then out and in again to get it into gear all the way. I notice mostly at low speeds like 25mph and less. I don't think 2nd is bad or syncros are going because when I beat on it and rip 1-2 it seems fine. Bad syncros seem like it would for sure be a worse issue the more load and throttle. I was wondering if the engine or trans were moving around some. That could cause the shifter to no line up properly also. I have also wondered about CAGS. I bought the car used 4 years ago and it was tuned out.

My cross member is tight, headers and x pipe all look good. I have poly shifter bushings that all look good, drive shaft and flex disk are all good. Drive shaft center support bearing seems ok. Shifter linkage is tight and seems good. Trans bushings and motor mounts look ok.

Kinda stumped at this point. Nothing has changed much with the car recently. I'll put it on the lift at work again Sat morning. Just not sure what else to check.

Deputy347k9 · 08-23-2018, 06:33 PM

I don't believe this is your problem but let me tell you what recently happened to me when taking my 1996 Impala SS (9,232 miles on the clock) out for a Saturday ride. In route to the Marine Corps Base Cherry Point, NC I applied the brakes when I immedietly heard a loud metal to metal noise? At first I thought the drive shaft might have fallen out, can't be because I have a safety loop. Pulled to the side of the road and looked underneath and found nothing. Car would go forward great until I hit the brakes? Brakes worked great in revers? Sounded like it was coming somewhere from the transmission area (I have a T56 six speed). MPs let me through the gate and I drove to a vacant parking lot. With the assistance of a young Marine I started jacking each corner and removing each tire. At the rear passenger I found the problem. The lower caliper bolt had backed out and disappeared! Marine to me to local parts store where I got a replacement one, bottle of lock tight. Drove to the base hobby shop and put the girl on the lift, removed each bolt and dressed them with lock tight and torqued to specs, no more problems.

dfwRobert · 08-23-2018, 08:43 PM

It’s gotta be a mount. I was driving around fiddling with it and notice a few things. The shifter moves back a lot when braking in neutral. The harder I brake the more it moves. If the shifter is moving back that must mean the bottom is moving forward. So it seems like the trans is moving up or the engine and trans are pitching forward.

IF it makes the popping noise it is hard to get into gear. If I stop slowly and no pop it seems to shift fine.

I see solid trans and or engine mounts in my future. But I will further diag first. I was hoping someone else had seen this.

BTW if you know if the “Cadillac Home Depot bushings” for the tr6060 work on our cars chime in. Thanks

h018871 · 08-28-2018, 08:21 AM

Pure speculation
Since the trans is tough to get into gear when you get a pop, I’d lean towards the trans mount/cross member area. Something is loose or cracked. It’ll be nice to know what you find

dfwRobert · 09-04-2018, 07:01 PM

Still no update really. I have had it on the lift 3 different times now checking. I've had the trans cross member out and all looks good. The trans mount looks pretty good. I lifted the trans up and down with a pole jack while the cross member was out to simulate back and forth movement. Nothing looks weird and engine mounts seemed ok when I did this.

The shifter bushings are all in good shape. The shifter is mounted solid. I nut and bolted the entire car. All suspension is tight. Guibo disc and driveshaft look good. Diff bolts are tight. I don't know what else.

Still does it though. If I easy brake all is fine. Med to hard brake from 30 plus and there is one single thunk you can easily feel in the shifter handle. I have wondered if something in the trans was funky. You would think If I have a bent shift fork or something else it would be constant and not dependent on braking and accel. Plus it does it in N. Also you would think anything internal trans would be exaggerated with faster shifting. I can give it the biz no problem and it shifts fine. It is more low speed parking lot stuff and in my neighbor hood that is the issue. I run factory fluid and have thought about swapping fluid but that wouldn't be the source of the clunk.

I will find it eventually and let everyone know.

dfwRobert · 09-19-2018, 12:44 PM

Quick update, I found a small leak from the drivers side engine mount. It is that blackish kinda looks purple hydraulic oil that drys up and is not really wet. I think that is why I didn't notice before. It was not wet.

I found a part# for the Z28 bushing for 82.00 on Amazon. They only had one so I still have to go to the dealer. Apparently the Z28 and Zl1 mounts are slightly different. I thought I read they are a little stiffer. Maybe not true but thought I would try them.

It will likely be a while before they are put on. I am going on Vacation next week and am getting last minute stuff done yada yada yada.

pump905 · 09-19-2018, 12:49 PM

Quote:

Originally Posted by Deputy347k9

I don't believe this is your problem but let me tell you what recently happened to me when taking my 1996 Impala SS (9,232 miles on the clock) out for a Saturday ride. In route to the Marine Corps Base Cherry Point, NC I applied the brakes when I immedietly heard a loud metal to metal noise? At first I thought the drive shaft might have fallen out, can't be because I have a safety loop. Pulled to the side of the road and looked underneath and found nothing. Car would go forward great until I hit the brakes? Brakes worked great in revers? Sounded like it was coming somewhere from the transmission area (I have a T56 six speed). MPs let me through the gate and I drove to a vacant parking lot. With the assistance of a young Marine I started jacking each corner and removing each tire. At the rear passenger I found the problem. The lower caliper bolt had backed out and disappeared! Marine to me to local parts store where I got a replacement one, bottle of lock tight. Drove to the base hobby shop and put the girl on the lift, removed each bolt and dressed them with lock tight and torqued to specs, no more problems.

I had this happen to me also

dfwRobert · 11-11-2018, 08:09 PM

Driveshaft u joint at the center support bearing!

So I replaced the engine mounts a few weeks ago. The Z28 ones looked identical to my SS ones. The drivers side was totally shot. Collapsed down and once out the top stud was like a kids loose tooth about to fall out. I felt a difference but still had the clunk and weird shifting issue.

Remember I said it makes a small clunk on med or higher accel then a loud thunk or pop on med braking. So I “set it” by accelerating in the parking lot at work. Then slowly babyed it in the shop with little to no braking. Once it was in the air I wiggled stuff around to see if I heard the noise. I put a pry bar between the trans and trans cross member and heard a pop from the center support bearing area. It was definitely e same noise I have been hearing. The u joint is rusty looking and binding.

It seems the u joint is not separately replaceable? I hate to have to buy a whole driveshaft. I’m still looking into in.

h018871 · 11-12-2018, 12:57 PM

Congrats on finding the issue!!!!
I had a local drive shaft shop change both the support bearing and u-joint. They could not balance it, but it does not shake any more

08-23-2018, 02:17 PM	#1
dfwRobert Drives: 11 2SS 6spd, 77 Trans Am, 13Audi Q7 Join Date: Apr 2010 Location: Frisco, Tx Posts: 38	Clunk when braking (not rear diff clunk) I have a clunking when braking mostly but also when accelerating. It is NOT diff clunk. Let me say I have had a full Prothane bushing kit out back including the diff bushings for over 2 years now. I hear diff clunk like a mofo all the time daily. I know THAT sound. This is different. This sound happens if you are slowing down from 20 plus and brake med to hard but not super hard. You hear one single thunk. It sounds like it is under the shifter. You can feel it in the shifter also if you keep your hand on it. To make the noise again I have to first take off kind of med to hard acceleration. If I was to baby the car from 0 out to 30 or 40 and try again I don't think it would happen. So in other words if I was going 40, hit the brakes hard then let off and tried to brake hard again it would not do it a second time. When I accelerate it will make a much softer thunk or clunk that is much harder to hear/feel. It is as if something is moving back and forth in the trans tunnel. Also it seems 2nd feels kinda weird at times. Like I have to pull into second and then out and in again to get it into gear all the way. I notice mostly at low speeds like 25mph and less. I don't think 2nd is bad or syncros are going because when I beat on it and rip 1-2 it seems fine. Bad syncros seem like it would for sure be a worse issue the more load and throttle. I was wondering if the engine or trans were moving around some. That could cause the shifter to no line up properly also. I have also wondered about CAGS. I bought the car used 4 years ago and it was tuned out. My cross member is tight, headers and x pipe all look good. I have poly shifter bushings that all look good, drive shaft and flex disk are all good. Drive shaft center support bearing seems ok. Shifter linkage is tight and seems good. Trans bushings and motor mounts look ok. Kinda stumped at this point. Nothing has changed much with the car recently. I'll put it on the lift at work again Sat morning. Just not sure what else to check. __________________ 2011 Black 2SS, 6 speed, AR long tubes, Borla S type full exhaust, Roto fab, prothane full bushing kit, Fe4 swap and 1le bars, 3.91s and a ton of other little stuff you can't see! No bling, wings, stickers, cool lights or junk without a purpose.

08-23-2018, 06:33 PM	#2
Deputy347k9 Drives: 2014 Ashen Gray Convertible Join Date: Apr 2017 Location: Havelock, NC Posts: 1,329	I don't believe this is your problem but let me tell you what recently happened to me when taking my 1996 Impala SS (9,232 miles on the clock) out for a Saturday ride. In route to the Marine Corps Base Cherry Point, NC I applied the brakes when I immedietly heard a loud metal to metal noise? At first I thought the drive shaft might have fallen out, can't be because I have a safety loop. Pulled to the side of the road and looked underneath and found nothing. Car would go forward great until I hit the brakes? Brakes worked great in revers? Sounded like it was coming somewhere from the transmission area (I have a T56 six speed). MPs let me through the gate and I drove to a vacant parking lot. With the assistance of a young Marine I started jacking each corner and removing each tire. At the rear passenger I found the problem. The lower caliper bolt had backed out and disappeared! Marine to me to local parts store where I got a replacement one, bottle of lock tight. Drove to the base hobby shop and put the girl on the lift, removed each bolt and dressed them with lock tight and torqued to specs, no more problems. __________________

08-23-2018, 08:43 PM	#3
dfwRobert Drives: 11 2SS 6spd, 77 Trans Am, 13Audi Q7 Join Date: Apr 2010 Location: Frisco, Tx Posts: 38	It’s gotta be a mount. I was driving around fiddling with it and notice a few things. The shifter moves back a lot when braking in neutral. The harder I brake the more it moves. If the shifter is moving back that must mean the bottom is moving forward. So it seems like the trans is moving up or the engine and trans are pitching forward. IF it makes the popping noise it is hard to get into gear. If I stop slowly and no pop it seems to shift fine. I see solid trans and or engine mounts in my future. But I will further diag first. I was hoping someone else had seen this. BTW if you know if the “Cadillac Home Depot bushings” for the tr6060 work on our cars chime in. Thanks __________________ 2011 Black 2SS, 6 speed, AR long tubes, Borla S type full exhaust, Roto fab, prothane full bushing kit, Fe4 swap and 1le bars, 3.91s and a ton of other little stuff you can't see! No bling, wings, stickers, cool lights or junk without a purpose.

08-28-2018, 08:21 AM	#4
h018871 Geoff Drives: 2020 ZL1 Green Join Date: May 2013 Location: Houston Posts: 1,719	Pure speculation Since the trans is tough to get into gear when you get a pop, I’d lean towards the trans mount/cross member area. Something is loose or cracked. It’ll be nice to know what you find __________________ Having a Blast https://www.camaro6.com/forums/showt...php?p=10741733

09-04-2018, 07:01 PM	#5
dfwRobert Drives: 11 2SS 6spd, 77 Trans Am, 13Audi Q7 Join Date: Apr 2010 Location: Frisco, Tx Posts: 38	Still no update really. I have had it on the lift 3 different times now checking. I've had the trans cross member out and all looks good. The trans mount looks pretty good. I lifted the trans up and down with a pole jack while the cross member was out to simulate back and forth movement. Nothing looks weird and engine mounts seemed ok when I did this. The shifter bushings are all in good shape. The shifter is mounted solid. I nut and bolted the entire car. All suspension is tight. Guibo disc and driveshaft look good. Diff bolts are tight. I don't know what else. Still does it though. If I easy brake all is fine. Med to hard brake from 30 plus and there is one single thunk you can easily feel in the shifter handle. I have wondered if something in the trans was funky. You would think If I have a bent shift fork or something else it would be constant and not dependent on braking and accel. Plus it does it in N. Also you would think anything internal trans would be exaggerated with faster shifting. I can give it the biz no problem and it shifts fine. It is more low speed parking lot stuff and in my neighbor hood that is the issue. I run factory fluid and have thought about swapping fluid but that wouldn't be the source of the clunk. I will find it eventually and let everyone know. __________________ 2011 Black 2SS, 6 speed, AR long tubes, Borla S type full exhaust, Roto fab, prothane full bushing kit, Fe4 swap and 1le bars, 3.91s and a ton of other little stuff you can't see! No bling, wings, stickers, cool lights or junk without a purpose.

09-19-2018, 12:44 PM	#6
dfwRobert Drives: 11 2SS 6spd, 77 Trans Am, 13Audi Q7 Join Date: Apr 2010 Location: Frisco, Tx Posts: 38	Quick update, I found a small leak from the drivers side engine mount. It is that blackish kinda looks purple hydraulic oil that drys up and is not really wet. I think that is why I didn't notice before. It was not wet. I found a part# for the Z28 bushing for 82.00 on Amazon. They only had one so I still have to go to the dealer. Apparently the Z28 and Zl1 mounts are slightly different. I thought I read they are a little stiffer. Maybe not true but thought I would try them. It will likely be a while before they are put on. I am going on Vacation next week and am getting last minute stuff done yada yada yada. __________________ 2011 Black 2SS, 6 speed, AR long tubes, Borla S type full exhaust, Roto fab, prothane full bushing kit, Fe4 swap and 1le bars, 3.91s and a ton of other little stuff you can't see! No bling, wings, stickers, cool lights or junk without a purpose.

11-11-2018, 08:09 PM	#8
dfwRobert Drives: 11 2SS 6spd, 77 Trans Am, 13Audi Q7 Join Date: Apr 2010 Location: Frisco, Tx Posts: 38	Driveshaft u joint at the center support bearing! So I replaced the engine mounts a few weeks ago. The Z28 ones looked identical to my SS ones. The drivers side was totally shot. Collapsed down and once out the top stud was like a kids loose tooth about to fall out. I felt a difference but still had the clunk and weird shifting issue. Remember I said it makes a small clunk on med or higher accel then a loud thunk or pop on med braking. So I “set it” by accelerating in the parking lot at work. Then slowly babyed it in the shop with little to no braking. Once it was in the air I wiggled stuff around to see if I heard the noise. I put a pry bar between the trans and trans cross member and heard a pop from the center support bearing area. It was definitely e same noise I have been hearing. The u joint is rusty looking and binding. It seems the u joint is not separately replaceable? I hate to have to buy a whole driveshaft. I’m still looking into in. __________________ 2011 Black 2SS, 6 speed, AR long tubes, Borla S type full exhaust, Roto fab, prothane full bushing kit, Fe4 swap and 1le bars, 3.91s and a ton of other little stuff you can't see! No bling, wings, stickers, cool lights or junk without a purpose.

11-12-2018, 12:57 PM	#9
h018871 Geoff Drives: 2020 ZL1 Green Join Date: May 2013 Location: Houston Posts: 1,719	Congrats on finding the issue!!!! I had a local drive shaft shop change both the support bearing and u-joint. They could not balance it, but it does not shake any more __________________ Having a Blast https://www.camaro6.com/forums/showt...php?p=10741733