usmcpony

I bought the car used with 1000 total miles on it. The car now has 3000 miles. I Was having issues with it shortly after buying it (long story) and now it'll only go in 3rd gear and no other gears. I'm at 780 rwhp and the tranny was supposedly built to handle 1000hp. I can't afford to do this again so it has to be right this time and whatever I decide to do the builder must warranty the tranny if it fails no questions asked. So, either im going to rebuild it again by a shop that'll stand behind they're work and their product or put a manual transmission in it. Id rather stay auto cause I really like the paddle shift. Any recommendations on a shop I can ship the tranny to that WILL fix it if their product fails or do I have other options? Is there another tranny i can put in it that will use the paddle shifters? I will not put in a boring auto that by-passes the paddle shifters. Im not turning this into a drag car.

ajrothm

Rossler transmission.

Circle D and Century are the other options...both known to have issues and warranty issues.

RPM wont touch a 6l80, otherwise they would be the best option.

Unreal

That being said, none of them last without a great tranny tune. Tune kills the 6l80s just as quick as anything else.

usmcpony

So my best two options aren't necessarily a good option? And whoever builds it will tune it.

realcanuk

Op, I feel your pain. When my stock trans gave up I agonized over the decision of what to do also. Spending 5 or 6k on a built trans is fine, if someone could guarantee it to be trouble free for at least a while. This doesn't seem to be the case from what I read.
It seems even the expensive built 6L80's are a bit of a coin toss. Some have great luck with them and some have problems.
For that reason, and because the cost and downtime of shipping back an forth being too much for me, after tons of research I chose to rebuild my trans with certain upgraded parts that I felt are necessary. I installed a good cooler, and I tune it myself. This is my second season on it and so far so good. Absolutely no issues. I will take it out this winter and refresh the clutches and steels, needed or not. The cost of that is minimal and I feel it is just routine maintenance on a car with 780 RWHP.
I am not super hard on the trans. I have minimal runs at the track with it so far but will be making plenty nearer to the end of the season. I never do full throttle kickdowns. Just the feel of that scares me.
Good luck with whatever you decide to do.

Unreal

Other option is to turn down the power to make it live longer.

Most of the builders of the high HP 6l80es don't tune them. You need to find a great tuner and leave on some torque management and mess with how it shifts or they like the blow up. Sucks that you can't fit a 6l90E in because that is what we did with a friends camaro. Lasted 2 years at ~780rwtq then started to slip. Put in a 6l90 and all good now.

Frans96ss

Its all in the tune.... But regardless no one will warranty it.... Period.

C6BOOSTED

My built 6l80E only lasted me 4k miles and I'm only making 600hp to the wheels. That was with their own transmission tune. So I sent it back to get it rebuilt and it still has issues. It flares on the 2/3 shift and 4/5 shift. If I could start and redo it again; I'll should of gone with a 4l65e or 4l80e.

Frans96ss

This is why we do so many of these swaps. If your car makes power and you want to race it this is your only option

0Presence Dist.

OP your PMs are full..clear them and send me a pm

subfloor@centurytrans

Uh, no.

So I guess the 390 passes and counting (as of last Wednesday) don't count huh? All of these by the way are with an average ET in the 10.20's and a 60ft time in the high 1.3's.

mdaniel

^This. And that goes for any aftermarket transmission.

I'd recommend the op call any number of trans builders and begin the conversation with 'I need a no questions asked warranty on my 750 hp Corvette'.

After he's done getting laughed at and hung up on by the trans builders he can decide how much money he's willing to **** away on a trans conversion.

It'll likely end up being less expensive to sell the car as it sits (or return it to stock and then sell it) and start over with a car that has the transmission type he needs.

Note that I did a T-56 to 4L60 conversion in my C5 and have been very happy with it. And if you can get a deal on the parts it's a viable option, but some of the price quotes I've seen mentioned ($10K+) are just not realistic IMO.

Frans96ss

So will you warranty the OP transmission?

usmcpony

They laugh at me and you bet your *** they won't get a cent from me. I have a $30,000 mustang with 650rwhp and a stock transmission that's been together for 30,000 miles. There's NO reason why my corvette with $100,000+ invested with a BUILT transmission should only last 2000 street miles! If their product can't handle what my car is making then they shouldn't sell me their product. Especially when they are anywhere from $5000 at the cheapest with me pulling the tranny and installing it. This ain't cheap! 10 builders may say they won't do it but one will. And if it holds I will spread the word and since there's probably 100 ppl wanting the same thing I'm wanting im sure this place will get allot of business.

ATLS2

After I spent a lot on getting the engine work, I spent equal amount on the trans and diff. RPM Level X 4l65 and stage 4 diff. Only thing I don't like is the trans controller that RPM uses. I think many people forget the trans until it's to late.

subfloor@centurytrans

He'll need to call Mike and discuss the particulars with him, that isn't my call to make.

realcanuk

Chris
With all due respect you seem to be the only one, or one of very few that gets that kind of life out of a 6L80. Could it possibly be something to do with HP levels rather than quarter mile times? Although your cars performance amazes me you are not supercharged and not at those HP levels. Maybe it's the big HP and torque that kill them faster.
Just thinking out loud here really.
Jody

subfloor@centurytrans

Unfortunately that's not quite true.

In the same manner in which you only ever seem to hear about LS7s when they blow up, the reality is there are thousands of engines out there that have never had any problems whatsoever.

We've done lots of 6L80s and had great success so far but as with any other type of high performance build, sh*t occasionally does happen. We are not however alone in this category because it would take me all of 5 mins to go on LS1tech.com and find several examples of people having different issues spanning builders, trans types and power levels.

Unreal

I just don't see the point of trying to make a 6l80 live when there are other great options. The only thing you give up is the paddle shifting which IMO is gimicky and doesn't help. Do a 4l65 or a 4l80 for the 750rwhp and enjoy it.

usmcpony

What is so different in the 6l80 that makes it fail so often even when built? Builders not using the right parts, not tuning it right, what's the deal? There's paddle shift exotic cars running 1400 hp. Why can the 6l80 do that?