bowflygsp

Made my dog happy. I had a '12 Avalanche before getting my '14 Silverado double cab. The Av, of course, had a bit more room in the backseat with the seats folded forward than the Silverado does with the backseat folded up. So I made a little platform for him (yes, he's pretty spoiled ). Started with on of these: http://www.homedepot.com/p/HDX-4-ft-Folding-Utility-Table-2448B-004/202599373 Modified by shortening two of the legs, removing the other two legs and some frame hardware. Added some indoor/outdoor carpet and installed. I also put the bottom half of a two-piece seat cover on the seat to help protect the leather. The platform also comes in pretty handy for other things too; groceries, luggage, fly rods, etc.

No, not at all. The shop foreman that I guess I insulted never said another word to me after our lil heated exchange. The service manager was ok, I guess, and the service specialist was pretty friendly. After they had swapped tires five times, swapped the drive shaft and finally found the ring and pinion to be out of spec, they tried to give the truck back to me until the new ring and pinion came in. They knew I had to go out of state for a couple weeks and the 'loaner' couldn't leave the state of Georgia. I basically refused to drive from Georgia to northern Michigan in a truck that they admit was out of spec. So they paid for my rental for two and half weeks and my truck was ready to go when I got back home. The service manager acted a little pissed about this, but if they just would've fixed it the first time I took it in instead of trying blow smoke up my ass, it wouldn't have been an issue.

January 2014 Ft Wayne, IN 3.42 gears Honestly, I'm not sure if they reinstalled the original prop shaft. I assume that they did, but the service report does not distinctly say it.

Here's an update on my truck. I had the vibration around 35-50 mph, especially during coasting/deceleration. The dealer originally told me it was due to the AFM switching from V8 to V4 mode. They also blamed the Bridgestone LT tires that I had replaced the Goodyears with. On the second visit, I explained to them that when the transmission was left in M5 mode, it had the same 35-50mph vibration even though the AFM stayed in V8 mode. The shop foreman then claimed they couldn't troubleshoot it anymore because of the LT tires. After some heated discussions, the shop foreman walking away & refusing to work on my truck, and me discussing with the service manager that I wanted to speak to the regional service rep and the dealership manager, they decided they would look at it again. Overall, they had the truck for over two weeks on this second visit and, according to the service report, this is what they did: Swapped tires with FIVE other trucks. Swapped prop shaft with another truck. Found rear end ring & pinion was 0.001" out of spec. Installed new ring & pinion. I picked up the truck last Tuesday and have put about 500 miles on it since. The 35-50 mph vibration is gone. Highway speeds seem to be pretty smooth. Again, I do have LT tires on it so I do feel the road a bit, but I can't complain about that. Overall, I wasn't happy about the process I had to go through to get this taken care of, but, as of today, I am satisfied that the issue is gone. Just thought I'd post a success story on here; doesn't seem to be many of them.

Just got a call from my dealership. They have swapped wheels/tires from a couple of different trucks. They swapped the driveshaft. Now they have ordered a new ring & pinion for the rear end but it won't arrive for a few days. They tried to get me to agree to have them put the truck back together and have me take it today but I refused. I am leaving for a 2000+ mile road trip from here in Georgia to northern Michigan and back later today and I'm not going to do that in a truck with a rear end that is suspect. I am going to head up to the dealership now and turn in my loaner so they can get me into an Enterprise rental for two weeks. The service manager even said he was not certain the ring and pinion would fix it so I figure they are going to need more time with the truck anyway. The saga continues.................

My truck that is in the shop right now is a 4WD, Z71, double cab, 6.5' bed, 3.42 rear end and has the 40-50mph vibration but not so much the highway speed (70+mph) vibration. The loaner truck I am driving right now is a 2WD, crew cab, 6.5' bed, unknown rear end and is silky smooth except it has a similar, but smaller magnitude vibration in the 20-30mph range. I do suspect there are certain combinations that are prone to certain vibration issues though. As I mentioned in an earlier post, I used to work for GM and still have contacts there. I was able to indirectly contact a driveline engineer at the Milford Proving Grounds that has been working on these trucks. When I supplied my VIN, the response was "the axle ratio and tire size are not the ones that have had vibration issues." This didn't help me much, but it seems to show that GM knows (or at least suspects) there is a certain combination prone to certain vibrations.

My truck (4wd Z71, double cab, 6.5' bed, 3.42) is back at the dealership for the second time in a week. I took mine in last Wednesday for the 40-50 (or 50-40) mph vibration. They said it was done the next day blaming the tires (aftermarket, larger diameter Bridgestone) with excessive road force and AFM. They told me the vibration when slowing down between 50-40 was due to the V4 mode and "deemed normal". Over the next couple of days I played around with the "manual" shift mode. I found that if I left it set at "M5", it never went into V4 mode, but it still has the 50-40mph vibration. Also noticed that, in regular auto mode, I could get it to go into V4 mode at around 70 but did not have a vibration there. That seemed to eliminate their claim that the AFM was to blame for the 50-40mph vibration. I went back to the tire shop Sunday morning to address the road force claim. The tire shop brought me out to their road force machine and showed me that the dealer had never removed wheel weights when doing the their test. They were very cooperative, stripped all weights off, tested and recorded road force values and rebalanced. All road force values were within spec for an LT tire. They even had their master tech take the truck for a drive and he suspected a powertrain issue (go figure). Monday morning, I am back at the dealership at 7am when the service department opens. They basically refuse to do anything because the tires were not replaced. I explained to them that I didn't care about the tire vibration. They still refused to do anything unless I basically bought new tires from them. I told them I am only concerned with the 40-50mph issue. They still refused. And on and on. I got pi$$ed. Some expletives were said and the shop foreman told his tech to pull my truck out of service and he was not going to work on it. That's I went to the service manager. I told him that I wanted to speak with the regional service rep and the dealership manager. Then he decided maybe they could look at it again. They still have my truck. From the update they gave me yesterday afternoon, they have swapped wheels and tires from two other trucks and have not figured out the issue. I mentioned that I used to work for GM and had suggestions from the driveline engineer in Milford to inspect the propshaft for dents and to index the propshaft at easy first steps. The dealer service rep claimed that was what they were looking at next. So, my experience so far seems to stay with the common theme over the nearly 90 pages on this thread; dealer claims "tires, tires, tires" until blue in the face, then maybe starts looking for the real issue.

Update on my double cab, Z71, 5.3, 4x4, 3.42: Took my truck to the dealership for the first time on Wednesday and told them about the vibration I was experiencing when decelerating from 50 to 40 mph or so. I got there and went for a ride with the shop manager. He said he noticed a 'tire vibration' and an 'engine vibration'. I have a leveling kit installed and larger than stock Bridgestone tires installed so I didn't expect much help with the tire vibration. Actually, the tire vibration never bothered me. As I had noticed also, he mentioned the engine vibration while decelerating seemed to happen when the AFM switched to V4 mode. When I left my truck with them after the ride, the manager seemed like he was going to really look into it. He said he would have to do some homework on the engine vibration. And that they would need the truck for 3/4 of a day to go through everything (including the vibration analyzer tool). That was at about 3:30p Wednesday afternoon. They called me at 10:15 am on Thursday saying my truck was ready. They claimed three out of four of my tires had excessive road force. They said they balanced them the best they could and that the vibration is much better but I should go back and try to get the tires replaced by Bridgestone because they were bad. When I asked about the engine vibration, he said it's normal. I explained that this is at least the third truck I have had with AFM I've never felt this before. I picked up my yesterday afternoon and, at first, it did seem like it was better. But driving to work this morning, the vibration decelerating around 50-40 mph is the same and now the truck shakes like hell at 70mph. It never did that before. So now I have to go to my tire shop and have them check the tires. I will try to play nice and do what the dealer says for this go-round, but this isn't off to a good start. In summary, by 'fixing' something that I wasn't concerned about they made it worse and they said the issue that I was concerned about couldn't be fixed. More to come......................

Silverado LT 4WD Z71, Double Cab, 5.3L, 3.42 rearend (I think), ~2200 miles OK, I have been watching this thread ever since I got home from the dealership when i bought my truck a month and a half ago. I first noticed the vibration about halfway home from the dealership and have experienced it pretty much everytime I have driven it since. The vibration I am experiencing is a little bit different from the others on here but I wanted to see what you guys thought. I would like to take the truck into the dealership next week or so and I want to have as much info beforehand as possible in case they are unhelpful. The vibration is most noticeable when coasting/decelerating from 55mph down to about 35mph. When accelerating from a stop up past 55 or 60mph, the vibration is not always noticeable, but it is consistently there if I slow back down to below 55mph. Then, if I accelerate again, the vibration seems to lessen but still noticeable until I get above about 55mph. I have had three different sets of tires on it (my own doing, not due to troubleshooting this issue) so I don’t think it is an unbalanced wheel or anything like that. It feels like a drivetrain vibration to me, but I’m far from an expert in this area. I can feel it in the floorboard and slightly in the gas pedal, but I do not seem to notice it in the steering at all. I am a bit concerned about the dealership being uncooperative due to the fact that I have a 2" leveling kit installed and swapped the Goodyears for Bridgestone Dueler A/T Revo 2 tires sized LT275/70R18. Has anyone with a leveling kit installed taken their truck to a delaership? If so, what kind of response did you receive? Like I said, I noticed this vibration the first day i owned the truck (before any modifications) so I know it is not related to the mods. Any suggestions or insight will be greatly appreciated. Thanks.

To each his own, but I'd rather have it look professional, not peel, etc. It's a $40k+ new truck, not a 20 year old beater. $100 is nothing considering the big picture.

Got my black billet bowties off Amazon. Made by Empire Vehicle Accessories. About $100 for the pair.

Got my black billet bowties off Amazon. Made by Empire Vehicle Accessories. About $100 for the pair.

2014 Silverado Double Cab Z71 4x4 Rough Country 2" level Bridgestone Dueler AT Revo 2 tires - LT275/70R18 Removed front air dam Removed "Silverado" & "LT" text badges Black billet bowties front & rear Extang Solid Fold tonneau DeeZee bed mat WeatherTech floor liners