Cadillac Owners Forum banner

Stock vs Lightweight Flywheel

18K views 39 replies 21 participants last post by  Twitch 
#1 ·
I have been having some vibration issues on my 2005 CTS-V and last night I took the transmission out of the car. I discovered that the dual mass flywheel is starting to come apart. I want to replace it but I am not sure which direction to go or what all of my options are, here is what I can currently get my hands on:

1. Stock replacement from GM dealer - $900
2. Lightweight replacement made from UUC - $425

I am concerned about losing tourque going with the lightweight replacement and I am concerened about the stock repalcement because I broke the original in 40,000 miles.

Any suggestions?
 
#2 ·
You probably won't find a UUC but go light non the less. It will take a little getting used to a lighter setup but you enjoy it much more. I say stick an LS7 setup in there if you're fairly stock.
 
#4 ·
I love my LS7 setup.
 
#6 ·
You will love the light flywheel.
 
#7 ·
Why you would want to stay stock is anybodies guess but if you do complete setups can be had on ebay brand new for $500ish.
 
#8 ·
I got a stock FW sitting on the garage floor. Good place for it, too. You don't want to go back to a stock FW. :nono:

Regarding driveability, I have no difficulty whatsoever driving a lightweight FW. You won't either.
 
#11 ·
The difference in cost for the whole LS7 set-up vs just the FW is negligible. Not to mention the minor difference in effort / labor to swap the FW vs. the whole clutch. Considering that you already have the whole clutch pulled out, you might as well replace the whole thing. I have been trying to make this decision myself, but will probably wait until my clutch goes completely or can't hold the torque. I am considering the LS7 from Lindsay, or the stage 2 from Monster. I have heard that you want to stick to a full face (avoid puck style - stage 3 and above) unless your car definitely exceeds the torque capacity of the stage 2 unit. I have been struggling with the decision to go light weight as well. Just remember, even the 28lb Monster FW and stock LS7 are still considerably lighter than the OEM dual mass turd. Some think the light weight 15 lb Monster FW is too light. Others absolutely love them. I think it probably just takes some time to get used to the change in engagement.
 
#12 ·
Perhaps I'm in the minority here but I picked up a new stock clutch for only a couple hundred bucks...i know its a turd but it was a good deal.. I'm still under warranty too so this is also cheap insurance in case of sudden failure. With all the stories of various clutches not working out, I didn't want to be under the gun..

I assume I can merry up a lighter flywheel with this setup and throw it in there if I have to..or just pass this one on to someone else.

I also don't know if I can give up my 2nd gear starts! Maybe when V isn't my dd anymore..

Ps_ any tips on how I can burn up my existing clutch on purpose? With all the wheel hop is it even possible?
 
#15 ·
Ps_ any tips on how I can burn up my existing clutch on purpose? With all the wheel hop is it even possible?
Clutch is a wear item and is not covered under warranty so I would think twice.
 
#18 ·
Pretty sure it was under $700 complete.
 
#22 ·
I just let my son drive... driver's ed age in Michigan is 14 and 8 months. Burned it up in no time :)

To be fair, it was already going so I thought it was a good time to have him practice.
 
#16 ·
The stock flywheel is an albatross. You will not loose a ft/lb of torque by going to the LS7 setup.
 
#17 ·
You'll gain it lol
 
#19 ·
Thanks for the answer to my question. My brother owns a performance shop in Atlanta, where I live, and he has been doing some research on the subject as well. He liked the idea of the LS-7 FW and clutch but he told me that it is still a dual mass and may not hold up to the "torture" of my driving style. He wants me to go for a single mass unit and he found a setup for me made by Centerforce. They make an aluminum single mass FW and clutch setup that is a direct replacement and the cost is around what I would have paid the GM dealer for a new stock replacement FW (without clutch). The Centerforce FW and clutch are a matched set so both are required. Here are the part numbers in case anyone is interested:
Clutch - DF612010
FW - 900143
 
#20 ·
If you are looking to do a whole new set up check out Monster Clutch. It's a direct replacement with slave cylinder and all. I recommend the level 2.

You can get it through Gforce who also sells the axles, drive shaft and soon the 9" rear. www.shop.gforce1320.com
 
#23 ·
When looking for a used LS7 set up, what should one be looking at specifically? Are there any tell tale signs of abuse, etc? Also, is the slave spacer the only "extra" we need on top of the clutch and flywheel? Oh, also, what kinda time should a mechanic be charging to do such a swap? 3-4 hours?
 
#31 ·
Check to be sure. But I'm 99% sure that if you get a C6 slave, you don't need a spacer.
 
#30 ·
When I did the UUC FW at about 47k miles, I left my stock clutch in. I didn't see it myself, but the guy who did the FW said the clutch looked just fine. I'd be surprised if it wasn't since I match RPM and tranny revs very closely when I shift so the wear should be minimal.

Guess I'm saying that if you shift hard frequently, doing the clutch, too, might be advisable.
 
#33 ·
Remember if you order from Luke at Lindsay, you get ls7 slave (requires no spacer).... I believe his entire kit is $635 plus shipping. Good deal. I'm certainly going that route when I get to it.
 
#36 ·
For any of you replacing a clutch. Make sure you buy the remote slave bleeder. I bought the LS7 clutch, PP FW and slave from Lindsay and yes it was 635 plus 40 for shipping to Ohio. It is not a dual mass FW and about half the weight. The job isnt all that difficult however 3.9 hrs I would say is only be if you have a lift and you've already done it before. Plus my exhaust bolts broke and I screwed around for 90 min getting the 4 bolts out of the flanges. I tried to save a few bucks and didnt buy the bleeder so this weekend I will be pulling it back apart to add the remote bleeder after installing the clutch two weeks ago. So repeating 4 to 5 hrs of work trying to save $80. Not worth it.
 
#37 ·
Well good news is it didnt take 4 hours. Pulled the trans added the remote bleeder and had it back together in about 2.5 hrs. But as I was wrapping it up and installing the shift knob then realized I had shoved the shifter back up through the floor 180 deg off. So luckily I was able to reach around the exhaust system and switch it without removing the exhaust. So after 3 hours it was back on the ground.
I would just like to say the LS7 set up is great I love it already. The hardest part will be taking it easy until the clutch is seated. It does wind up noticeably quicker and I wanted to really get on it. But I drew from every little bit of self restraint and have babied it for now. So glad I did it.. The remote bleeder was great and I like the idea of being able to flush dirty clutch fluid at any time too.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top