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I am going to start this posting by saying that I don’t like to cry “wolf” unless I am pretty sure there IS one, and also by acknowledging that we might simply have an isolated example here. But since I simply don’t know, and Chevrolet doesn’t seem to either, I thought I should post an alert to our members, and let’s see if it’s a fluke or another “SSR problem”.
IF:
You see any evidence on your chassis of a transmission fluid leak, or
You have begun to hear a peculiar sound that gets louder as road speed increases, or
You have begun to feel a “shake” or vibration that is speed related rather than engine rpm related,
And, especially if your SSR has been retrofitted with the newest “anti-ting” aluminum driveshaft (recognizable by the “donut” at its front end),
You might want to head down to your local Chevrolet dealer and politely ask that they inspect:
- Your transmission tailshaft seal for leakage
- The amount of diametral (NOT rotational) “play” in the front end of the driveshaft (i.e. don’t twist it, but rather push it upward & see how much play)
- Your driveshaft YOKE for (a) quality of finish, and (b) amount of play
Let me amplify a bit.
The leakage would show as spray on the tailshaft or transmission crossmember, and might include actual droplets if it has progressed far enough. This is probably the first easily verifiable symptom.
The noise is difficult to describe. It is rather easily dismissed by even a very normally alert & trained driveline mechanic as “just rear end noise because of the high axle ratio used in this vehicle”. However, a particularly astute listener will clearly be able to discern that this noise is SEPARATE from rear end gear noise, and does NOT come from the rear end, but rather from right under the passenger cabin. It is VERY hard to describe. The best words that come to mind are:
- “Ringing” sound
- “Hollow” sound
- “A sound somewhat similar to tire noise on a highway” (and therefore easily dismissed as such)
- “Air rushing at very high speed past metal” (like wind noise through a sheetmetal structure)
It also gets quieter as the vehicle warms up at highway speed.
It may disappears or attenuate greatly for a few miles if ONLY the tailshaft seal is replaced, as a cure for the leak, but returns quickly.
The “shake” or vibration when it happens can become apparent rather quickly (like overnight it seems), can be felt in your steering wheel, can be seen somewhat by attempting to watch the side mirror for shake, and can be felt by a passenger. It appears to occur in only a narrow road speed range (NOT engine rpm related). It can easily be misdiagnosed as tire imbalance. If you reach this point, take your vehicle in SOON, as this is a destructive symptom that occurs late in the game.
I am kicking myself a bit for not being firmer with the Chevrolet dealership that installed my new “tingless” donut-equipped driveshaft, and for not putting all the pieces of apparent evidence together sooner.
I got that new tingless driveshaft installed by a Chevy dealer when I complained about the “tinging” (If you don’t know what I am talking about, just type “ting” into the search feature on this website). I had the SSR sound system on that day and didn’t pay attention to the new driveshaft as I drove over to Lamar Walden Automotive for some unrelated work, at city speeds.
Lamar remembers that day very clearly, because I told him that I had just gotten the new driveshaft installed, and he was interested enough to examine it. He was puzzled by 2 features. One was the donut on the front end of it. The other thing that really bothered him is that it felt like it had way too much play in it (diametral, not rotational) when he grasped it to examine the amount of rotational u-joint play. He and his son Rob both agreed it felt way too loose, just like it would feel if it were old and worn out. They mentioned it to me at the time, but I assumed that Chevrolet knows what they are doing, and I knew it HAD to be a new driveshaft because this donut design did not exist before. Lamar commented on it AGAIN when I picked up the vehicle, remarking “that just is too loose”. I did return to the Chevrolet dealership days later and noted it, but was told that while that amount of play might seem “loose” it probably was fine, and that the noise I was hearing was “rear end whine”. I accepted that because I am certainly no car mechanic.
Ever since I got that driveshaft, I have had that noise described above, sometimes quiet and sometimes louder. But the only ones who ever thought enough of it to mention it were Lamar and Rob. Even Buffy, who rode in the SSR with me and even drove it, never thought it was THAT unusual. Like me, he attributed it to what we had both heard from others: just rear end gear noise from the high ratio, and maybe just a hair more backlash in the rear end gears than is really needed, or something.
Along the way, I even had Lamar make two changes that we thought MIGHT reduce noise, as we both assumed that the lightweight aluminum driveshaft makes a pretty good “musical amplifier” of ANY noise created anywhere in the driveline, and I dislike unnecessary noise. We changed the rear end lubricant to a costly formula that is known for its ability to both lubricate and silence rear ends, and he got the driveshaft foamfilled and precision balanced for me. The lubricant did quiet down the rear end a bit, and the foam had a bigger positive impact (I now see why in retrospect – the noise source was at the FRONT of the driveshaft, not the rear). One of my next “planned projects” in my efforts to make my SSR more perfect was to get either Lamar or MTI to recheck and possibly tighten up the rear end gear backlash, to see if that would make things quieter yet.
That was the situation until late last week, when I took the SSR into a (different) Chevrolet dealership for a routine oil change, since Lamar was unavailable to do it at the time. While walking under the “quick lube” rack during the oil change, I (not the mechanic) noticed transmission fluid on the crossmember. A service advisor was called over, and he agreed that there was a leak, and that its cause needed to be determined.
The next day, I brought the SSR in, and within an hour or so, it was returned to me with a new tailshaft seal installed in it. The service advisor agreed that a tailshaft seal failure at only 8500 miles seems awfully odd, but everyone assumed that the original seal had perhaps just been installed badly at the factory.
On the way back to work from the dealership, I noted something very different about the sound of my SSR. I could now clearly hear a normal gear whine from the high ratio rear end as coming clearly from the rear, and that “other” sound I had been hearing was GONE. Because I WANTED to believe that the seal may have been the problem all along, I didn’t really ask myself if it was reasonable to believe that a bad seal could have caused that noise that was now gone.
Going home from work, in hindsight, I made another error. I drove home on city streets, where the low speed had NEVER produced that strange sound (always became audible only at speeds over about 35 mph). Thus, I missed the fact that something changed again.
That something was that the noise returned! I found that out the next day, maybe 30 miles later, when driving on the highway again. More disturbingly, I now also had a shake that occurred in only one speed range (around 65 to 70 mph). To eliminate the most likely possible cause, I had my tire balance checked right away, as I assumed that I COULD have hit a pothole or something that knocked one of them out of balance. The balancing technician though assured me that he found nothing amiss.
When I told Reese at MTI about it, he offered to go on a test ride with me, and quickly confirmed this was driveline related, not engine related. He put the SSR onto a hoist to check to see if there was anything obviously amiss on the chassis, and found that the transmission seal was again leaking. Oops. Reese pointed out that replacing the seal alone had been a futile act on the part of the dealership, since SOMETHING ELSE had likely destroyed it.
I went back to the dealership. 4 hours of diagnostics later, including the use of a spectral vibration analyzer, they were mystified. So, I called both Lamar and Reese who independently both advised the exact same thing: Check both the yoke and the bushing at the driveshaft / transmission meet point. I passed that information on to the Chevy service advisor in a phone message, and also left another message about Lamar’s earlier observations about the diametral looseness of the connection. Bingo.
In my next conversation with the service advisor, he told me that I would need to keep the loaner Malibu until at least early next week! He told me that the technician who was working on my SSR, after hearing the information I provided in the messages, did some detailed checking, and declared that the driveshaft needed replacement, that the seal needed replacement, that the tailshaft bushing was undamaged, but that the yoke looked, and FELT, like it had always been oversize and had never been correctly finish machined. He had already ordered an entire new driveline forward of the rear axle, by the time I called. That’s where we are at right now, waiting for the new parts to arrive.
Side comment at this point: Steve Waters, are you SURE it is your SSR’s rearend that is the problem causing YOUR symptoms? Ask your dealership to check YOUR yoke play, size, and finish.
This is a frustrating thing to have happen, but as I think about it, I can’t really fault anyone. Lamar tried to warn me that my driveshaft was not “right”. The first Chevy dealership unfortunately misled me, but in all honesty, how can you blame a driveline technician when he assumes that a brand new part, specifically designed to address a known driveshaft issue, is ITSELF not right. Same thing for the second dealership. While theoretically they COULD have found the problem the first time, on a probability basis this problem is probably as common as a meteor hitting the Earth, since (a) it’s pretty weird, and (b) there aren’t exactly millions of SSRs out there for mechanics to get experience on. And, I have to say to their credit, once Lamar’s and Reese’s comments got them looking at the right stuff, they moved quickly to order replacement parts, and told me to hold onto the loaner car. I think that’s a reasonable response.
I also speculated about the possible sequence of events. The new driveshaft assembly was either defectively machined or possibly incorrectly spec’ed at the design stage. For whatever reason, the front end of the assembly was loose enough to move around a lot. The new metal donut, probably intended as a dampener, instead acted as a hammer weight that wore the crap out of the already oversize joint. That movement and wearing would:
(a) make noise under the passenger compartment (!!)
(b) kill the seal FIRST (because it is the most fragile part in the assembly)
(c) Then, start to progressively build ever greater wobble into the joint, until when worn enough, and at the right frequency on the road (65 mph in my case), we get a sympathetic shaking of the whole vehicle (a drive shaft, even an alloy one, is heavy, and especially destructive with a metal donut right beside the point of wobble)
The sound probably was greatly reduced right after the first seal was replaced because the new seal buffered the play until it TOO got destroyed like the first seal.
I am waiting to see what happens next.
In the meantime, if the above symptoms have occurred on anyone else’s SSR, please ping me at:
[email protected]
More information and confirmation could help Chevrolet figure it all out IF this is not just an unfortunate isolated incident of “one bad assembly”, but rather a batch.
No one should assume at this point, unless and until shown otherwise, that this is anything but an unfortunate isolated incident. I could really have gotten the only one, or one of a very few, that got out of the manufacturing process not quite right. We’ll see.
Jim G
IF:
You see any evidence on your chassis of a transmission fluid leak, or
You have begun to hear a peculiar sound that gets louder as road speed increases, or
You have begun to feel a “shake” or vibration that is speed related rather than engine rpm related,
And, especially if your SSR has been retrofitted with the newest “anti-ting” aluminum driveshaft (recognizable by the “donut” at its front end),
You might want to head down to your local Chevrolet dealer and politely ask that they inspect:
- Your transmission tailshaft seal for leakage
- The amount of diametral (NOT rotational) “play” in the front end of the driveshaft (i.e. don’t twist it, but rather push it upward & see how much play)
- Your driveshaft YOKE for (a) quality of finish, and (b) amount of play
Let me amplify a bit.
The leakage would show as spray on the tailshaft or transmission crossmember, and might include actual droplets if it has progressed far enough. This is probably the first easily verifiable symptom.
The noise is difficult to describe. It is rather easily dismissed by even a very normally alert & trained driveline mechanic as “just rear end noise because of the high axle ratio used in this vehicle”. However, a particularly astute listener will clearly be able to discern that this noise is SEPARATE from rear end gear noise, and does NOT come from the rear end, but rather from right under the passenger cabin. It is VERY hard to describe. The best words that come to mind are:
- “Ringing” sound
- “Hollow” sound
- “A sound somewhat similar to tire noise on a highway” (and therefore easily dismissed as such)
- “Air rushing at very high speed past metal” (like wind noise through a sheetmetal structure)
It also gets quieter as the vehicle warms up at highway speed.
It may disappears or attenuate greatly for a few miles if ONLY the tailshaft seal is replaced, as a cure for the leak, but returns quickly.
The “shake” or vibration when it happens can become apparent rather quickly (like overnight it seems), can be felt in your steering wheel, can be seen somewhat by attempting to watch the side mirror for shake, and can be felt by a passenger. It appears to occur in only a narrow road speed range (NOT engine rpm related). It can easily be misdiagnosed as tire imbalance. If you reach this point, take your vehicle in SOON, as this is a destructive symptom that occurs late in the game.
I am kicking myself a bit for not being firmer with the Chevrolet dealership that installed my new “tingless” donut-equipped driveshaft, and for not putting all the pieces of apparent evidence together sooner.
I got that new tingless driveshaft installed by a Chevy dealer when I complained about the “tinging” (If you don’t know what I am talking about, just type “ting” into the search feature on this website). I had the SSR sound system on that day and didn’t pay attention to the new driveshaft as I drove over to Lamar Walden Automotive for some unrelated work, at city speeds.
Lamar remembers that day very clearly, because I told him that I had just gotten the new driveshaft installed, and he was interested enough to examine it. He was puzzled by 2 features. One was the donut on the front end of it. The other thing that really bothered him is that it felt like it had way too much play in it (diametral, not rotational) when he grasped it to examine the amount of rotational u-joint play. He and his son Rob both agreed it felt way too loose, just like it would feel if it were old and worn out. They mentioned it to me at the time, but I assumed that Chevrolet knows what they are doing, and I knew it HAD to be a new driveshaft because this donut design did not exist before. Lamar commented on it AGAIN when I picked up the vehicle, remarking “that just is too loose”. I did return to the Chevrolet dealership days later and noted it, but was told that while that amount of play might seem “loose” it probably was fine, and that the noise I was hearing was “rear end whine”. I accepted that because I am certainly no car mechanic.
Ever since I got that driveshaft, I have had that noise described above, sometimes quiet and sometimes louder. But the only ones who ever thought enough of it to mention it were Lamar and Rob. Even Buffy, who rode in the SSR with me and even drove it, never thought it was THAT unusual. Like me, he attributed it to what we had both heard from others: just rear end gear noise from the high ratio, and maybe just a hair more backlash in the rear end gears than is really needed, or something.
Along the way, I even had Lamar make two changes that we thought MIGHT reduce noise, as we both assumed that the lightweight aluminum driveshaft makes a pretty good “musical amplifier” of ANY noise created anywhere in the driveline, and I dislike unnecessary noise. We changed the rear end lubricant to a costly formula that is known for its ability to both lubricate and silence rear ends, and he got the driveshaft foamfilled and precision balanced for me. The lubricant did quiet down the rear end a bit, and the foam had a bigger positive impact (I now see why in retrospect – the noise source was at the FRONT of the driveshaft, not the rear). One of my next “planned projects” in my efforts to make my SSR more perfect was to get either Lamar or MTI to recheck and possibly tighten up the rear end gear backlash, to see if that would make things quieter yet.
That was the situation until late last week, when I took the SSR into a (different) Chevrolet dealership for a routine oil change, since Lamar was unavailable to do it at the time. While walking under the “quick lube” rack during the oil change, I (not the mechanic) noticed transmission fluid on the crossmember. A service advisor was called over, and he agreed that there was a leak, and that its cause needed to be determined.
The next day, I brought the SSR in, and within an hour or so, it was returned to me with a new tailshaft seal installed in it. The service advisor agreed that a tailshaft seal failure at only 8500 miles seems awfully odd, but everyone assumed that the original seal had perhaps just been installed badly at the factory.
On the way back to work from the dealership, I noted something very different about the sound of my SSR. I could now clearly hear a normal gear whine from the high ratio rear end as coming clearly from the rear, and that “other” sound I had been hearing was GONE. Because I WANTED to believe that the seal may have been the problem all along, I didn’t really ask myself if it was reasonable to believe that a bad seal could have caused that noise that was now gone.
Going home from work, in hindsight, I made another error. I drove home on city streets, where the low speed had NEVER produced that strange sound (always became audible only at speeds over about 35 mph). Thus, I missed the fact that something changed again.
That something was that the noise returned! I found that out the next day, maybe 30 miles later, when driving on the highway again. More disturbingly, I now also had a shake that occurred in only one speed range (around 65 to 70 mph). To eliminate the most likely possible cause, I had my tire balance checked right away, as I assumed that I COULD have hit a pothole or something that knocked one of them out of balance. The balancing technician though assured me that he found nothing amiss.
When I told Reese at MTI about it, he offered to go on a test ride with me, and quickly confirmed this was driveline related, not engine related. He put the SSR onto a hoist to check to see if there was anything obviously amiss on the chassis, and found that the transmission seal was again leaking. Oops. Reese pointed out that replacing the seal alone had been a futile act on the part of the dealership, since SOMETHING ELSE had likely destroyed it.
I went back to the dealership. 4 hours of diagnostics later, including the use of a spectral vibration analyzer, they were mystified. So, I called both Lamar and Reese who independently both advised the exact same thing: Check both the yoke and the bushing at the driveshaft / transmission meet point. I passed that information on to the Chevy service advisor in a phone message, and also left another message about Lamar’s earlier observations about the diametral looseness of the connection. Bingo.
In my next conversation with the service advisor, he told me that I would need to keep the loaner Malibu until at least early next week! He told me that the technician who was working on my SSR, after hearing the information I provided in the messages, did some detailed checking, and declared that the driveshaft needed replacement, that the seal needed replacement, that the tailshaft bushing was undamaged, but that the yoke looked, and FELT, like it had always been oversize and had never been correctly finish machined. He had already ordered an entire new driveline forward of the rear axle, by the time I called. That’s where we are at right now, waiting for the new parts to arrive.
Side comment at this point: Steve Waters, are you SURE it is your SSR’s rearend that is the problem causing YOUR symptoms? Ask your dealership to check YOUR yoke play, size, and finish.
This is a frustrating thing to have happen, but as I think about it, I can’t really fault anyone. Lamar tried to warn me that my driveshaft was not “right”. The first Chevy dealership unfortunately misled me, but in all honesty, how can you blame a driveline technician when he assumes that a brand new part, specifically designed to address a known driveshaft issue, is ITSELF not right. Same thing for the second dealership. While theoretically they COULD have found the problem the first time, on a probability basis this problem is probably as common as a meteor hitting the Earth, since (a) it’s pretty weird, and (b) there aren’t exactly millions of SSRs out there for mechanics to get experience on. And, I have to say to their credit, once Lamar’s and Reese’s comments got them looking at the right stuff, they moved quickly to order replacement parts, and told me to hold onto the loaner car. I think that’s a reasonable response.
I also speculated about the possible sequence of events. The new driveshaft assembly was either defectively machined or possibly incorrectly spec’ed at the design stage. For whatever reason, the front end of the assembly was loose enough to move around a lot. The new metal donut, probably intended as a dampener, instead acted as a hammer weight that wore the crap out of the already oversize joint. That movement and wearing would:
(a) make noise under the passenger compartment (!!)
(b) kill the seal FIRST (because it is the most fragile part in the assembly)
(c) Then, start to progressively build ever greater wobble into the joint, until when worn enough, and at the right frequency on the road (65 mph in my case), we get a sympathetic shaking of the whole vehicle (a drive shaft, even an alloy one, is heavy, and especially destructive with a metal donut right beside the point of wobble)
The sound probably was greatly reduced right after the first seal was replaced because the new seal buffered the play until it TOO got destroyed like the first seal.
I am waiting to see what happens next.
In the meantime, if the above symptoms have occurred on anyone else’s SSR, please ping me at:
[email protected]
More information and confirmation could help Chevrolet figure it all out IF this is not just an unfortunate isolated incident of “one bad assembly”, but rather a batch.
No one should assume at this point, unless and until shown otherwise, that this is anything but an unfortunate isolated incident. I could really have gotten the only one, or one of a very few, that got out of the manufacturing process not quite right. We’ll see.
Jim G
