Does anyone have a link or photo of the ZL on a lift to see the suspension driveline

[55Designs]

[QUOTE=paul2010;3993198]I wonder why mine didn't ever have this problem.

You mentioned all stock bushings these absorb harmonics easily and if you haven't calibrated your speedo with the 370 gears your 135mph pass is more like 115 or so. Also the springs you are using really aren't slamming the cars they are modest lowering which for this car is the best but try telling that to guys who refuse to listen especially paying customers we deal with all the time.

[paul2010]

[QUOTE=55Designs;3993372]

Originally Posted by paul2010

I wonder why mine didn't ever have this problem.

You mentioned all stock bushings these absorb harmonics easily and if you haven't calibrated your speedo with the 370 gears your 135mph pass is more like 115 or so. Also the springs you are using really aren't slamming the cars they are modest lowering which for this car is the best but try telling that to guys who refuse to listen especially paying customers we deal with all the time.

Yes it has been professionally calibrated by Lingenfelter Performance Engineering and won second fastest 5th Gen two years in a row at the LSX Shootout. It ran a 9.84 at 144 in the 1/4 mile. I don't think the speed checker at Lucas Oil Raceway, Muncie Speedway, Gateway and several others are off.

[OldJedi]

Originally Posted by 55Designs

1.Reason is many have this issue and have given up trying to chase the fix.
2. Look at the number of low mile cars modified on the market, wonder why? I spoke to well over 80 owners and they all said that's why they were selling.
3. Most owners will never experience this issue or drive well beyond 100+

its a bad driveline vibration from the negative angles of the diff and axles. when you mod the cars or lower them it becomes worse, stiffer bushings also make it worse as do larger tires.

Axles seem to break Outer CV even aftermarket ones, driveshaft couplers wear and break and even suspension bolts over time become loose.

every race car has this issue. GM really messed up and I want to see what and how they mad the ZL1 into what it is. GM knows of this problem since I have spoken to engineers since 2009 and said they planned to fix for the 2012+ models.


So once i get a chance to see a ZL1 in person I will immediately know what they changed.

I would pose this question to Justice Pete from Pedders. I do not know who else has more time under a Gen5 Camaro or has more knowledge of it's suspension.

[2SSRS@Gen5diy]

There was a thread from a member on how to raise the dif to help with the angel on the Axles.

[JusticePete]

Pedders has been lowering ZETA vehicles starting with the Holden Commodore in 2006. The ZETA (Commodore and Pontiac) and ZETA II (Camaro) respond very well to suspension and other modifications in Australia, England and the USA. Our L/28 ran the OPTIMA Challenge last Saturday with no unusual vibrations. The L/28 has an LPE diff, HD half and drive shafts. Aside from the nasty rip of the custom built LPE LS7, it is as docile as puppy.



We have run the Pedders USA Camaro at the OPTIMA Challenge, tested every suspension component we sell and some that didn't make the cut on her as well as recording Z06 lap times as shown in this video. The driveline in our Pedders USA Camaro was bone stock. Not a single failure of any OE driveline parts and certainly no unusual vibrations in the driveline.




In AU, Pedders has an eXtreme VE Commodore. As you can see in this photo it is lowered just a bit. They run road courses with three different world class rally drivers behind the wheel. There are no unusual vibrations. It even has a TRAILER HITCH.





We ran the living daylights out of the Pedders USA G8. With boosted power, 275/35/19s all around on a bone stock driveline it performed flawlessly for the 20 some odd thousand miles I abused, err owned it along with several clones that were arguably driven harder.





When you lower a 5th Gen Camaro, the differential remains in the same position it was at OE ride height. It doesn't change. It is bolted to the sub-frame. The sub-frame does NOT change position when the car is lowered. It is bolted to the monocoque. The position of the control arms and half shaft angles do change.

The biggest issue with the half shaft angle change due to lowering is heat. The grease used in the OE shafts will liquify and leak out on track days. Companies like the Drive Shaft Shop use lube compatible with the higher temperatures. OE shafts can be 'upgraded' with the higher temperature lube.

I have personally installed Pedders lowering kits on more than 50 5th Gens. Last night we installed a full Justice Suspension on a 5th Gen. The front ride height is 642mm and the rear is 650mm. There is absolutely not a single unusual vibration in the car. This is the typical result. A few have incurred half shaft failures, but those are directly attributed to massive increases in RWHP and tires with far more sticktion than OE. This is a key point. OE testing is done with OE tires. Changing the tire compound changes everything. Tires are the fuse in OE vehicles. The tires spin and smoke in a no harm no foul event. Put drag radials or road course slicks on the car and you have raised the value of the fuse. It is no different than replacing a 20 amp fuse or circuit breaker with a 40 amp fuse and wondering why the wire over heated. As far as racing a 5th Gen, in my opinion that is very different than a street car. When you go racing, if you're not breaking you're not running hard enough or long enough. That in no way is indicative of a OEM design flaw.

Again, this is what we at Pedders have seen since 2006. It doesn't make us right. It makes us Pedders.

[55Designs]

Alot of guys do not hit the high speed zone long enough to ever notice. Almost every Grand Am driver I spoke to and the crews that build the Camaros told me every single car vibrates and they constantly replace diffs, axles and other stuff after each race since certain tracks have longer straights and shake things apart. I think these race engineers should know a thing or two which is why they raise the differentials. even the crew chiefs told me its the design of the car and there are only certain things you can do to overcome this. This is obvious why GM made the suspension so sloppy from the start with horrible bushings and sub-frame and differential movement to absorb these harmonics. When I drove a 5th gen stock for the first time I always wrecked it the car felt loose and horrible i couldn't believe it was so bad.

the only time I ever drove a 5th gen at super high speed and it was perfectly smooth was with the raised diff, and PS2 tires. Im talking 145-170mph range.

Another thing to consider with 3 inch exhaust, headers, big motors and cams and loud gears the car is so loud and obnoxious most wont even think something is wrong. this also only affects V8 Manual cars and if you look at the numbers, a majority of production are V6 and Automatics.
I am still sticking to my notion that the geometry of the sub-frame could have been much better and I would like to see how GM made changes.


Funny how there are THOUSANDS of low mile 5th gen Manual V8 for sale right now even the special tuner modified ones and nobody is selling them.

[JusticePete]

We have had our Pedders USA ZETAs over 150 MPH many times. No problems. That has nothing to do with the race cars that have been built by race car builders. If the 5th Gen has an issue as a race car, the race car builder needs to sort it out. Nothing a race car does is reflective of a GM design flaw.

I have said this since I first drove a Commodore in AU, my first G8 and first Camaro. Bone stock they drive really well. Once of the primary criteria in the Camaro program was to build a library quiet car as import buyers equate quiet with quality. The Chevrolet design team worked very hard to reach that level of expectation. The number of conquest sales and female buyers is an indication of how well they did their job. It is my privilege to know and have work with a good number of GM engineers. Most of them race their own cars. They are hard core car guys that I respect.

I am not saying the 5th Gen is perfect. Our business is based on taking bone stock cars to a higher level of performance. Yesterday I had the opportunity to install a full Justice package on a 5th Gen with FI. I cut the front sway of a 2012 Camaro in half to see what the wall thickness was on the 2012 front bar. The OE bars are made of thick wall tubing that many aftermarket sway bars sellers would love to boast about. It is a very good bar. We make stronger bars to make the car do the things we want it to do. That doesn't make the OE part bad. It makes our part different.

I am not surprised to see built Camaros languish in the market. My personal built cars don't sell particularly well. It seems many buyers are put off by our use of the cars and some call it abuse. One all the 'special' equipment is installed the build costs are staggering. There are some twin turbo threads on this forum that are so over the top I am awestruck. The amount of time the owners devote to the builds is matched only by the money they have spent. My guess is they know when they start the build they stand little chance of getting their money out.

As for changes made by GM you are talking about the ZL1? Those that are expecting the ZL1 to be very different from the standard build Camaro I think they will be disappointed. Driveline components have been beefed up, but still mount in the same locations. If a 5th Gen owner orders a lower rear control arm Chevrolet will ship one with the old style inboard sway bar mount and the new style FE4 / ZL1 mount today. None of this is insider information from anyone at GM. It is information that is available publicly. I saw this photo posted some time ago. I saved it. Good thing because the thread and pictures were quickly deleted.



This ZL1 'spy shot' could have been an ordinary 5th Gen with a ZL1 body, but the color of the MR dampers says otherwise. There is nothing really different under the ZL1 other than refinements to handle more power with a factory warranty. Once again, I could be dead wrong. Economics indicate I would be more right than wrong. There is no way it could be cost effective for Chevrolet to produce a special monocoque for a ZL1 to accommodate a different sub-frame design.

I have no doubt that there are race cars with serious vibration issues or that others have experienced a problem with the stock car or modified builds. Where we disagree is that the issue is a design problem. I would love to get my hands on a 5th Gen with the vibration issue along with some time to sort it out. It is what I have learned after I knew it all that I take satisfaction in.

[ChuckD]

Those racecars also use solid metal subframe "bushings". In other words, they don't use bushings. It's no surprise their driveline is suffering.

I saw the anodized "bushings" on one of the Grand Am Camaros being repairered post-race (after a collision) at Mid-Ohio this year.

[55Designs]

Originally Posted by JusticePete

I have no doubt that there are race cars with serious vibration issues or that others have experienced a problem with the stock car or modified builds. Where we disagree is that the issue is a design problem. I would love to get my hands on a 5th Gen with the vibration issue along with some time to sort it out. It is what I have learned after I knew it all that I take satisfaction in.

Pete we have access to 8 cars locally if you ever want to drop in the NY area. Also look under the section for TSB and Warranty issues. This is becoming a much more common issue even on 2011+ cars right from the dealers lot. its beyond frustrating and has been the most annoying thing to troubleshoot for customers.

The only time I ever had such an issue was with a 2008 Mercedes E63 AMG. from day 1 that car vibrated from the rear from 65+mph. After a lengthy battle in court when every single part was replaced it was confirmed the hand built AMG engine had a defective crank shaft which also caused the cams and other parts to wear and fail. That engine knocked so loud since the vibration just cause premature wear of all the rotating parts. AMG engineers flew from germany with some serious high tech gear to confirm this. i only wish GM had and would take such initiative.
Could this be an engine issue on an LS3 I have no idea how to even initiate such a test. We always checked tailshaft for run out on everyones car and all was within spec. Changed, diffs, driveshafts, axles, rims, tires you name it. Some stuff makes it better others worse or the speed where it comes in changes. engineers keep pointing fingers at the cars platform and pinion and axle angles. Im just a frustrated tuner after all the wasteful hours we spend on this. I have 3 customers holding on to their 2010-2011 to trade for the ZL1 but are all worried.

[JusticePete]

New York is not on my fly and test drive list until the spring thaw

If you know of a car in Florida or Texas I'll be in both areas through the end of the year. I did post in one thread with a Texas based car. Sooner or later I'll get one in a Pedders shop with all the required equipment to run through as many variables as possible.