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2004 vs 2006 rear diff.

8K views 30 replies 21 participants last post by  brngrhd 
#1 ·
I'm looking at 2 V's this weekend. 04 & 06. Is the 2006 rear diff any better than the 2004 ? I know the LS2 is nicer than the LS6, but I'm more concerned about the rear diff, as I will tracking the car, rather hard. Auto-x, Road course, maybe a drag strip or 2.

The 06 is $10K more expensive, but less mileage.
 
#2 ·
The original differential in a 2006 V is a better dramatically better unit than the original differential in a 2004 V. Many 2004 Vs however, no longer have their original differential and a 2004 V could have the latest differential (released in early 2008 as a replacement part), which is still better than a 2006 original unit.

The 2006 V also has other improvements. I love my LS6, but if I were buying a used V I would look first and the 2006s and 2007s.
 
#10 ·
The LS2 has a larger displacement which comes in handy under modifications, makes more torque across the powerband stock, revs to the same RPM as the LS6, and generally puts down more usable power on the dyno.

However, I'll have to agree... for 10k more, you can get an 8.8 setup and be solid in comparison to the '06, then you can save the remainder for a cam setup and assist that tiny feeble infantile 5.7 liter into making real world power.

[edit]
I'm sorry gentlemen, figured I'd start this one up.
 
#14 ·
How much mileage difference is there? If they are kind of close, get the cheaper one and spend the extra $10k on mods. If the '06 has a lot less miles (half?), I'd go for the '06.
 
#16 ·
Lol how is someone expected to buy a car without a test drive? I mean OK if you insurance doesn't cover a potential buyer then make a deal like if you have cash in hand you can test drive it and if you don't like it I'll give your cash back and you can leave or something. I had a 17 year old come to test drive my last car and with almost 400whp at the front tires I wouldn't let him just come drive it. Being that he was a noon at driving I was certain he would put my car into a wall
 
#17 ·
Not sure how an 06 is worth 10k more than the 04. My 06 can't be worth more than 17k (98k miles)...doubt you can buy the 04 with the same milage for 7k. I would look for a good deal on the 06 myself. Never had a rear diff problem for what its worth.
 
#18 ·
get an 06. Be prepared to travel. Got my 06 half way across the country. Got the plane ticket for $200 and drove it back for $200 in gas. Was an awesome trip and well worth the travel. Got it for less than what I could find locally in my big city, it's a rare enough car if you see the deal you need you want elsewhere travel out with cash or a bank check and scoop it up.
 
#20 ·
:coffee:There are four different part numbers for the differential of a V1.
1st --- 10361308 in '04
2nd--- 10368780 in '04 & '05
3rd--- 15793756 installed in '06 & '07.
4th--- 25873498 was released in 2008 for a slight improvement over 15793756

None of these rears are suitable for repetitive Drag Racing due to the Design, ie., aluminum case, support structure.

:yup: G-force axles are advisable or equivalent.

:yup: Find out what the diff part # is on the '04 :suspense: '06
 
#21 ·
#24 ·
Ok I just bought my car 2004 cts-v I was told it "had the newer rear end installed" so I searched on here found this thread with part numbers and checked mine based off these numbers. Had a fellow technician who works at the dealership with me check the number too. We came up with 15793758 when I search that number here I come up with nothing..... If I google it I come up with an 05 SRX rear end..... Is it normal to do that swap? Is it any stronger/weaker then the cts stuff?
 
#25 ·
I don't know why the last number is an 8 instead of a 6, but I'm pretty sure you have a 3rd gen diff there. As far as I can tell, all of the individual components of the 15793758 diff and the 15793756 diff are the same. Which means it was replaced at some point. Could be wrong though.
 
#27 ·
I was under the impression that one of the changes made from the 3rd gen to the 4th was the pinion seal. I thought there was a recall back in like '07 recalling them because of a leak. If that's true, then it makes sense that yours would have the old style. I don't have access to a dealership computer or anything, and I'm sort of new to these diffs, but that's the story I know.

Experts on the issue: if I'm spouting lies, let me know.
 
#29 ·
Yes I had read that, and just read it again, my diff number is not listed on here anywhere.... If i google it I do come up with a SRX diff which seems to be a possible swap for the car..... My question come more to the point of "if it looks like the old diff am I to take that it is weak like the old style diff? And is it only the most current diff that has the updated seal/pinion support?
 
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