who has broke a 4l80e
05-08-2009, 10:21 PM
#11
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Reaction carrier planetary bit the dust... Thank you B&M for a plugged trans cooler...
Parish8 snapped an input shaft but I believe at that point he was over 900rwhp and was still locking the converter during shifts...
05-08-2009, 10:34 PM
#12
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The 4L80E is a clutch to clutch transmission when its in OD range. There are no bands to slip, bang, hold, not hold (unless in manual 1st, 2nd and I think 3rd) and make inconsistant shifts. The pump is better, cast iron non variable style. Line pressure in theory stays more stable because the only thing in control is the Pressure Control Solenoid. Its just a better transmission all around.
05-08-2009, 11:40 PM
#13
Actually bands are generally considered to be stronger than a clutch set .
The 3-4 cluthc for instance is no competitor to the 2-4 band.
But IMO the point is any trans can be broken and the 80e well looking at numbers is not indestructable. Dont get me wrong its a strong trans and stronger than the 60e but its breakable. What you need depends on the power range you have and use. in some cases the 60e is indeed better and in others the 80e preferred
The 3-4 cluthc for instance is no competitor to the 2-4 band.
But IMO the point is any trans can be broken and the 80e well looking at numbers is not indestructable. Dont get me wrong its a strong trans and stronger than the 60e but its breakable. What you need depends on the power range you have and use. in some cases the 60e is indeed better and in others the 80e preferred
05-09-2009, 03:52 PM
#14
well what would i need behind a 370 with a tc78 at 210kpa and that new edelbrock ls xt manifold? if a 4l60e will do it great, as long as i can get one that shifts on point! in fact i would prefer it do to me new yank sc3200 billet converter.
05-09-2009, 08:57 PM
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I could have gotten by just fine with a built 4L60E but I got into this 4L80E for 600 bucks and thats including the transmission, shift kit and all. I couldn't pass that up.
05-10-2009, 10:54 AM
#16
Locking the converter with any trans during shifts is IMO crazy the inpact to the internals is like beating the inside with a sledge hammer take and part from any trans and get out the ten pound sledge and start beating then when you see the damage multiply that times 10 and thats whats happening inside your trans.
05-10-2009, 11:00 AM
#17
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I still don't see the point of shifting with a locked converter. My converter brake stalls to 1500 on a good day and my shifts are pretty harsh as is. I can't imagine shifting at WOT on a locked converter.
I could have gotten by just fine with a built 4L60E but I got into this 4L80E for 600 bucks and thats including the transmission, shift kit and all. I couldn't pass that up.
I could have gotten by just fine with a built 4L60E but I got into this 4L80E for 600 bucks and thats including the transmission, shift kit and all. I couldn't pass that up.
The idea is to get to the end of the track in as little time possible... A sliping converter is a huge wast of time and energy...
I have yet to see a converter that completely locks up during shifting, hard on trannys....uuuu HELL ya....
05-16-2009, 01:41 PM
#18
The weakest point in the 4L80-E I've found is the roller clutch in the overdrive. This thing holds torque in all gears except fourth. The one I toasted was the 2001+ redesigned type with the little shoes that prevent the rollers from skewing. The downside to the current design is the the rollers and overall assembly diameter are both smaller. Chuck from FLT has mentioned this before and had voiced his preference for the 2000 and prior design roller clutch.
When mine blew a few months ago I did three things to try to prevent this again int he future:
- swapped back in my 2000 model year roller clutch assembly.
- softened all upshifts by lowering baseline line pressure.
- reinstalled 10" 3500+ converter. (was running a stock 350 converter with the 454)
The first time it slipped was on a WOT 2-3 upshift. That upshift is the most difficult for the roller clutch to hold against. After that first slippage happened it went downhill from there over a four-day period. Looking at these photos it is a miracle it still sort of "worked" and got me home.
(In case anyone's wondering, I wouldn't normally yank the engine to work on the trans! It came out anyway for top end swap.)
Roller clutch Current Design:
Roller Clutch pre-2001 Design:
When mine blew a few months ago I did three things to try to prevent this again int he future:
- swapped back in my 2000 model year roller clutch assembly.
- softened all upshifts by lowering baseline line pressure.
- reinstalled 10" 3500+ converter. (was running a stock 350 converter with the 454)
The first time it slipped was on a WOT 2-3 upshift. That upshift is the most difficult for the roller clutch to hold against. After that first slippage happened it went downhill from there over a four-day period. Looking at these photos it is a miracle it still sort of "worked" and got me home.
(In case anyone's wondering, I wouldn't normally yank the engine to work on the trans! It came out anyway for top end swap.)
Roller clutch Current Design:
Roller Clutch pre-2001 Design:
Now if I can just get a damn converter that's right 