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Discussion Starter #1
Has anyone here replaced their rear differential in the base model?

I am seriously wanting to do this, but I don't know if I should go with a 3.27 or 3.45 limited slip. I would really like some input on this one. I have done about everything I want to do to this car other than a engine swap. I was going to do it this year but summer is already half over so it will have to wait until next year. Intake, exhaust and tune. I'm not going to bother doing any more mods to the V6.

BUT... I figured I could change the rear diff and that would help a bit in the meantime. I'm not looking to track the car or anything like that but I would like some improved get up and go, especially from a dead dig.

I know the changes in pipe diameter throughout my exhaust system has hurt some of my low end power. The guy from Magnaflow told me it would. Sure enough it did.

I also do a bit of highway driving, so there's that to think about. Just not sure which rear gear to go with.

The 3.27 gear sounds like the ticket, but would you really even feel a difference from 2.92? It's a small change imo. The old timers I've talked with all say to go at least a full step in gearing. The 3.45 is only a half a step.

So does anyone have any ideas on what would work best overall? I'm pretty sure more than a few guys with the V6 has done this.

I would love to hear some input if you have. Thanks.
 

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I'm in the same boat as you. I want to swap a diff into my V6 and have been looking into it a lot. From what I've seen both the 3.27 and 3.45 work. Personally I will probably go with the 3.27 because it seems like a nice improvement that won't raise the rpms on the highway too much. I'm currently on stock tune for everything. I'm hoping I can get a performance trans tune from Overkill that's adjusted for the 3.27. I'm not going to do the overkill engine tune until I have all the bolt ons I want now done. Intake an exhaust already done, manifold spacers from Mace came in the other day. Debating on weather or not to try headers. I'll link a video i found with someone who put a 3.27 in their V6. It looks like it has pretty good pickup.

 

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I went from 3.70 to 3.91 and it was most definitely noticeable. Don't let the fact that it seems like a small step on paper scare you. I would go with the 3.27 in your case as it would provide an improved get up and go like you are looking for without increasing your cruising RPM too badly.
 
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Discussion Starter #4 (Edited)
I'm in the same boat as you. I want to swap a diff into my V6 and have been looking into it a lot. From what I've seen both the 3.27 and 3.45 work. Personally I will probably go with the 3.27 because it seems like a nice improvement that won't raise the rpms on the highway too much. I'm currently on stock tune for everything. I'm hoping I can get a performance trans tune from Overkill that's adjusted for the 3.27. I'm not going to do the overkill engine tune until I have all the bolt ons I want now done. Intake an exhaust already done, manifold spacers from Mace came in the other day. Debating on weather or not to try headers. I'll link a video i found with someone who put a 3.27 in their V6. It looks like it has pretty good pickup.

I was going to do all that... intake manifold spacers, headers, etc. Hell I even thought about doing the cams that Mace has for the LY7, but in the long run...why? Seems nobody is ever really satisfied with the performance the V6 gives. A Supercharger would be perfect but not feasible as far as cost goes. I just decided that I will do the V8 swap and be done with it. As far as the rear end goes, I would want to probably change it regardless of what engine I had.

Fortunately, I can do the differential swap at the shop I work at. That way, anything I may need will be right there for me. I want to cover all my bases before I start. I was thinking although I don't have any problems, I should probably check and replace the center support bearing if needed. Also the seals for the axles at the diff. The 3.27 I was looking at only had 56k so the bushings are still in good shape, or so I was told. I guess if they need to be changed, I'll probably go with poly.

The job itself should only take a few hours. It's not rocket science. From what I understand, I need to use the yoke from the V6 diff.

Unfortunately, my tuner is a few hours away from me, so I'll have to drive it in manual mode until I can get to him.
 

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Discussion Starter #5
I went from 3.70 to 3.91 and it was most definitely noticeable. Don't let the fact that it seems like a small step on paper scare you. I would go with the 3.27 in your case as it would provide an improved get up and go like you are looking for without increasing your cruising RPM too badly.
Yeah it sounds like the 3.27 is the way to go. Do you think the rpm's would be too high at cruising speeds on the highway with the 3.45?
 

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Yeah it sounds like the 3.27 is the way to go. Do you think the rpm's would be too high at cruising speeds on the highway with the 3.45?
I don't think they would be too high necessarily but the juice ain't worth the squeeze. Your V6 isn't going to be a drag car and 3.45s would be a bigger hit to gas mileage. 3.27s would balance the two nicely.
 
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I was going to do all that... intake manifold spacers, headers, etc. Hell I even thought about doing the cams that Mace has for the LY7, but in the long run...why? Seems nobody is ever really satisfied with the performance the V6 gives. A Supercharger would be perfect but not feasible as far as cost goes. I just decided that I will do the V8 swap and be done with it. As far as the rear end goes, I would want to probably change it regardless of what engine I had.

Fortunately, I can do the differential swap at the shop I work at. That way, anything I may need will be right there for me. I want to cover all my bases before I start. I was thinking although I don't have any problems, I should probably check and replace the center support bearing if needed. Also the seals for the axles at the diff. The 3.27 I was looking at only had 30k so the bushings are still in good shape, or so I was told. I guess if they need to be changed, I'll probably go with poly.

The job itself should only take a few hours. It's not rocket science. From what I understand, I need to use the yoke from the V6 diff.

Unfortunately, my tuner is a few hours away from me, so I'll have to drive it in manual mode until I can get to him.
I'm only 17 so a V8 swap isn't in the question for a while lol. I'm going to work with what I've got and try to get the most out of the engine and car as a whole for now within reason. Other than the exhaust, intake and manifold spacers there isn't much left that won't be a bigger project. As far as headers I don't want the Pacesetter because apparently they hang low at stock height, if i lower the car that would be a hassle. I believe any V6 Camaro shorty headers fit but i honestly don't know if it's worth the effort. New diff would definitely be worth the cost, I'm just hoping a local shop can do it for me. I like to do what I can on my own but it seems like more than I can do in my driveway.
 

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Bang for the buck diff swap would be at the top of my list if I was so inclined but have resisted the temptation so far.
JonDom02 made a very valid point there isn't much left that is going to make a huge difference in HP.
Sadly our V6's aren't as tuneable as the V8's not matter how many parts we throw at them.
That's why mine is bone stock.
Not knocking or dissing other V6 owners who have tried to upgrade for more HP, your braver than I am.
 

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V6’s are tuneable, it is the fact it is only 60% of the displacement of the 6.0 V8. You want V8 performance it’s turbo or blower. Now getting the V6 to make 300+ HP is not hard and respectable.
A good handling, 300+ HP car would any drive time better.
More gear and posi is just what they need.
 
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Discussion Starter #11 (Edited)
They are definitely tuneable. Mine has been tuned and will be getting tuned again after the differential swap.

I picked up a 3.27 limited slip from a 2015 SS Camaro today with 56K on it. Bushings look new but I will change the seals just for good measure.

It's being shipped to my shop so I will probably do the swap next weekend.
 

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They are definitely tuneable. Mine has been tuned and will be getting tuned again after the differential swap.

I picked up a 3.27 limited slip from a 2015 SS Camaro today with 54K on it. Bushings look new but I will change the seals just for good measure.

It's being shipped to my shop so I will probably do the swap next weekend.
Let us know how it feels after with the new diff. I'm hopefully doing new plugs and intake spacer soon just waiting on the plugs to arrive from Rockauto. I'd like to do the diff soon but at this point I'm going to drive it as is for a while because I miss driving it so much. Haven't been able to drive it for over a month because the front brakes started grinding and CarID and Powerstop messed up the order twice. First I was waiting for over 2 weeks and even got a shipping confirm for a brake kit, called when it didn't ship and it turns out it was never in stock even though it was on the site. Ordered a different set and waited another week only to have a set of rears and the wrong fronts. Finally gave in and just ordered the individual Power stop rotors for the front from a different site so I have a matching set and I'll send the wrong ones back to CarID. Lesson learned and I'll go with G8Only next time.
 

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Discussion Starter #13
Let us know how it feels after with the new diff. I'm hopefully doing new plugs and intake spacer soon just waiting on the plugs to arrive from Rockauto. I'd like to do the diff soon but at this point I'm going to drive it as is for a while because I miss driving it so much. Haven't been able to drive it for over a month because the front brakes started grinding and CarID and Powerstop messed up the order twice. First I was waiting for over 2 weeks and even got a shipping confirm for a brake kit, called when it didn't ship and it turns out it was never in stock even though it was on the site. Ordered a different set and waited another week only to have a set of rears and the wrong fronts. Finally gave in and just ordered the individual Power stop rotors for the front from a different site so I have a matching set and I'll send the wrong ones back to CarID. Lesson learned and I'll go with G8Only next time.
Glad to hear you got your brakes all worked out. I put new brakes on when I first got the car towards the end of 2018, but since then I put Brembos on the front and very glad I did. I was never really happy with the brakes on this car but with the Brembos on its a night and day difference.

You should really consider getting your car tuned to get 100% out of what you put into it. I know for me, after I installed a cold air intake, catch can, x pipe and Magnaflow axle back, my car was throwing cel's for running lean. I could have chased, changed and spent a ton of money on O2 sensors to get the cel off or get it tuned and get a little better performance and mileage out of the deal. Getting it tuned was one of the best things I've ever had done to it. The timing was advanced, he bumped up my idle from 600 to 700 which I like a whole lot better, fuel trims, shift points, etc.

Anyways, I will report back to let everyone know how it went. I'll try to get some pictures as well.
 

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Glad to hear you got your brakes all worked out. I put new brakes on when I first got the car towards the end of 2018, but since then I put Brembos on the front and very glad I did. I was never really happy with the brakes on this car but with the Brembos on its a night and day difference.

You should really consider getting your car tuned to get 100% out of what you put into it. I know for me, after I installed a cold air intake, catch can, x pipe and Magnaflow axle back, my car was throwing cel's for running lean. I could have chased, changed and spent a ton of money on O2 sensors to get the cel off or get it tuned and get a little better performance and mileage out of the deal. Getting it tuned was one of the best things I've ever had done to it. The timing was advanced, he bumped up my idle from 600 to 700 which I like a whole lot better, fuel trims, shift points, etc.

Anyways, I will report back to let everyone know how it went. I'll try to get some pictures as well.
Did you get the CTS-V Brembo kit? I heard that's what a lot of people upgrade to. I'll probably get a bigger brake kit in the future. My Dad has a 2014 ATS 2.0T and it comes with factory Brembos that are bigger than the ones on my G8. It stops that thing on a dime.

Tune is definitely something I'm going to do once all the bolt ons I want are done. Still debating on headers and a bigger throttle body.
 

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In my extremely humble opinion, CARiD has atrocious business practices in virtually every sense of the word imaginable.
 

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In my extremely humble opinion, CARiD has atrocious business practices in virtually every sense of the word imaginable.
After what I went through, I kinda have to agree. I can't put all the blame on them because it's Powerstop's fault for shipping the wrong brakes the second time around. But the first set I ordered was "in stock" online, little did I know it was on backorder for months which I was never told until I called. Called in agian to see if a Baer brake set was in stock because they claimed it was on the website but also no. Finally I ordered the other powerstops that ended up showing up wrong. To CarIDs credit everyone I talked to was helpful and understanding but the money I saved getting these over something else wasn't worth the time wasted and down time of the car. Still in the process of returning things to them but so far neither company has offered any sort of deal to me for all of this. I'm not expecting much but a discount or something would be nice because at this point just sending me the correct item isn't making up for anything. That's what should have happened the first time not 6 weeks later.
 

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Am still owed a refund that was promised/guaranteed on two occasions by at least two customer service representatives. They shipped a package which was halfway across and days later before the tracking number populated. Contacting them through eBay was akin to watching paint dry in the winter. (n)(n):(
 

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Discussion Starter #18
Personally, I would not deal with that place. Just looking at their site tells me there would be problems.

I pieced my front Brembos. Bought the calipers from Amazon and the Raybestos 355 mm rotors and Akebono pads from Rock Auto. The correct caliper bolts I ordered through the dealer thru my shop. One of the best upgrades I've ever done to my G8.
 
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