I have a level 6 4l60e from a top builder. It’s always had a 2-3 shift flare, but I’m thinking it’s not going to last a lot longer.

converter is a yank pas 3400.

Engine combo is a 377 with 20 psi peak via overspun Procharger D1x.

Car is a 2004 GTO.

Id like to keep a 4l60e if it’s possible.

Do you think an upgrade to a level 7 or 10 4l60e can survive at this power or is it time for a built 4l80e?

 

Following

 

if you paid good money for a "level 6" and it's always flared...something doesn't feel right

I'm up in NW iowa. I see both of you guys are from Iowa as well.

Shoot me a PM if you wish. We deal with high HP 60e stuff

Full disclosure, there may be times when it's more financially sound to swap to a 4l80e. Or some guys just prefer the overkill nature of the 80e. and that's perfectly fine.
We do big power 80e as well.

That said...a healthy 377 at 20 psi I would hope should make near the 800hp ballpark. a 60e CAN live at that power level. But it will need a good list of parts and alot of attention to the hydraulics.
Best of luck to both of you guys

 

This is a couple years ago. First night at track with the 377 was on about 14 psi at this time. You can hear the flare on the 2-3 shift. It hasn’t gotten any worse at 20 psi. More pressure on the tune on the 2-3 did nothing. Smoke is tire smoke from the burnout still rolling out. Never been on a dyno car is on e85 at 10.6 to 1 static compression. I do my own work and tuning, but i know nothing about building transmissions. I also use meth injection and a btr intake as the other changes since the video.

https://m.youtube.com/watch?v=YQoO-kMJcDM

 

so what (roughly) does it run at eddyville?
I'm familiar with the track

 

I'd rather not say. I haven't ran it yet at 20 psi yet just street tuned. I hope to go within the next few weeks for a test and tune. It's easily 800+ rwhp. I'm spinning the D1x 4000 rpm over max recommended impeller speed...lol.

 

OK
short answer given the amount of info, is that the 80e will likely be a worthwhile way to spend your money and get plenty of reassurance that you have a trans you don't have to worry about
That said, the 60e can be made to live if you're hard-set on keeping it. Just get the checkbook ready

 

Im running 416cu D1x overspun on my Level 7 4l60..... so far so good knock on wood

I was in same position as you that I did not want to switch to 80 due to high dollar converter

 

Absolutely talk to MaroonMonster as he is one of the true experts here.
While a 4L80E is a good choice for 800 rwhp, it won't be cheap either - a JY trans won't hold up; you'll have to buy at least a moderately built one. Plus torque converter, driveshaft and electrical changes.

 

I would think the torque of the larger motor would be harder on the trans. How long have you been running it?

A freshen up/upgrade to level 7 from the same builder is certainly my cheapest option. Looking at the parts list between a level 6 and 7 the primary difference in parts seems to be just the input shaft. I would also think if I told them the issue was a 2-3 shift flare that they could fix that during the upgrade.

 

.........that should of been fixed the first go around. IMO

 

I don’t disagree. I didn’t make a big issue of it 3-4 years ago when I got the trans so it’s pointless to make a big issue of it now. All I can do is mention it and see if they can address it on a rebuild.

If I would of made a big deal of it day one and they told me to pound sand I’d feel differently. I don’t know how they would of treated me on it because I didn’t make a big deal of it or insist they make it right.

 

2k ish hard miles.

Yes the 6 and 7 difference from same builded was the input shaft.

I also have a slight 2-3 shift flare as well however not sure if that is tune related.

 

Hmm...I may just live with it then if it doesn’t get any worse. I’m not sure what changes between a level 7 and the next thing up the level 10, but at that price point the 4l80e starts to make more sense.

 

Just trust me on this one. You might wanna pay any money for MaroonMonsterLS rebuilding your 4l60e.
his knowledge is absolute and his 4l60e will behave way more superior than a stock 4l80. If GM find his developments, the whole engeneering team will drop theyr jaws.

Just do it.

 

Whether you go 4L60E or 4L80E matters not if Grady in your home state is the one building it.
He can build you any "level" 4L60E or 4L80E that you need.

 

I am a long time 4l60 hater, but I will say that the internals can be built to handle enough to rip off the tailshaft. Until you hook good enough to rip off the tailshaft, a 4l60 CAN be built to work. Whether it is worth the hassle is another question, although I have to admit that all the 4l80 fanboys rarely tell you how many times they welded clutches together. If you do decide to upgrade, be aware a few hammer blows to the GTO transmission tunnel are a required part of a 4l80 upgrade. It is not a simple tune and electrical issue, although it is not that difficult either.

 

Who or where is "Grady"?

 

Grady is @MaroonMonsterLS1

 

Ok I sent him a Pm.