2004-2007 Cadillac CTS-V General Discussion Discussion, rear end noise in Cadillac CTS-V Series Forum - 2004 - 2007; Hi, I just purchased an 07V and it does have a light howl in the rear end. Usually nothing bad, ...
Hi, I just purchased an 07V and it does have a light howl in the rear end. Usually nothing bad, but I did a moderate launch today and it really started howling (almost screeching) at some speed. So I stopped and put it in reverse for a second to set the lash back (i don't know, the only thing I could think of). And the screeching went away.
Is this rearend totally fubared or can I can just rebuild it with new bearings? Do the cases warp on these? Will an 09 pumpkin fit in? Any help/advice is appreciated.
This is the most asked question here, most well known and documented issue with the car you just bought. You'll need to do some searching here. Your warranty or lack thereof should have been explained to you prior to purchase, if it wasn't that points to "none". Virtually all stock diffs whine, if it's howling badly it is damaged in some way- like mine. You can probably drive on it forever that way if you aren't launching the car and it's a newer 25xxxxx series. There are three solutions currently, GFORCE 9" kit for $5500, Creative Steel 8.8" kit for $4250 I believe, and a new stock diff for around $1600 that may or may not be noisy out of the box. Welcome, take comfort in the fact that you are not alone and that there are extensive discussions on this topic.
If the first dealer you go to says no, move on to another. Some dealers will deny you right out of the box. Others want the work. I took mine in for a fluid change, and they replaced the whole carrier.
mine had no trouble replacing it when i explained the noise. just tell them what it is doing, and they will know what is wrong... make sure they know you know it is a problem.
It is worthwhile to note that if it only happens when you are actually on the gas pedal (even slightly) that is a good indicator it is the rear, and not another drive line. My first diff would start whining around 42 mph, you could just lightly touch the gas pedal to make it whine then let off and nice and quite...
Why do the rear ends go out? Is it really the rear end (differential) or a wheel bearing or cv joint? Mine howls weather you have you foot on the gas or not. You just have to be moving down the road. It is very loud. I have no leaks at all. Could I add some special oil or something to it? Where are you Timmy C?
The rear end becomes noisy from the pattern of wear on the ring and pinion gears. The earlier units (pre-2006 model year) also suffered from poor case design that led to breakage in some cases and in gear misalignment in others. The primary causes of gear wear in the more recent units are failure to break-in the unit when new, over loading when cold (the splash lubrication system is ineffective at lower temperatures) and heat-induced lubrication failure. My original unit became noisy and used oil analysis indicated copious amounts of gear metal. The noise it produced varied in tone, pitch, and loudness based on whether the car was accelerating or decelerating and rate of said acceleration and deceleration. If the noise you are hearing does not vary with throttle application it may well be something else - wheel bearing being one candidate.
Since mine howls when on the gas at all in 5th or 6th at speeds appropriate for high gears, does a fluid change help at all or is it not significant? Mine's an '04 with 121,00 on it. Not sure of the history so I'm assuming stock everything for parts save for my intake and I'm interested in getting new fluids this summer. Worth my time for diff fluid?
Changing the fluid is unlikely to cure the howl, but it may extend the life of the unit. Typically, the friction modifier that keeps the limited-slip clutches from sticking together in corners deteriorates before the fluid itself. Some have reported some quieting effect going to a higher viscosity gear oil.