Mail order 4L80E?

[Texas82GP]

Opinions Wanted!

Guys,

The 4L65E in my truck is dead, again. It failed on a wide open throttle 1-2 upshift Wednesday morning, on my way to work. I think it shattered the output shaft, since it is leaking transmission fluid out of the tailhousing seal. It has been built twice in 50k miles. At 120k the 3-4 clutches were toast. At 135k the input shaft was pulling out of the input drum and was leaking pressure, which resulted in burned up clutches. I'm not sure I want to fix it again. I'm considering a 4L80E swap.

My truck is a 2008 GMC Sierra regular cab, short bed, two-wheel drive. It has a 5.3 with the GM LS Hot Cam, headers and a tune. It has 4.10 rear gears with 32" tall tires. I'm guessing it puts out maybe 400HP and 400ft. lbs. at best at the flywheel. I'm guessing it weighs 4500 lbs. (based on internet research). I'm keeping this truck (presumably until I croak) and a more powerful engine in the future (after the Grand Prix runs and drives) is not unlikely.

If I were to go with a 4L80E, I was considering just mail ordering one that is already a performance build, for the convenience. The sky is the limit on price though. I don't think I want to spend $5k on a mail order transmission.

I have a buddy that manages an automatic transmission parts house on the other side of town where I grew up. He knows several builders. He can help me line up the parts and a builder to beef up the 4L65E some more or to build up a 4L80E. He sent me a parts list for an 80E build. It's $900 without hardened shafts. If I spend another $1200 (random number in the range I've seen) on a core, then I'm $2,100 + money for the builder into it which is pretty competitive with the mail order transmissions, especially considering I don't have a core. Then I need a flexplate, torque converter, lower bellhousing, dipstick tube and indicator, shift cable bracket, etc., etc. An 80E swap will be expensive but I'm up for it since I'm keeping the truck.

What I don't want is to spend another $2k on the 4L65E and break it again, or to spend $3k+ on an 80E swap and break that when another $500 spent would have made the difference.

A few questions for you guys:

1. Is anybody on here running a mail order 4L80E? If so, which one and what has been your experience like? What is your power level and how hard do you drive it? How many miles?

2.How strong is a stock 4L80E?

3. Should I be worried about a hardened input shaft or output shaft or other key hard parts in the 80E? I can't imagine ever putting north of 600HP in the truck and closer to 500 is more likely. I've been thinking along the lines of a naturally aspirated 370 c.i. build or maybe even a 408 stroker in the future.

4. If it was your truck, what would you do? I drive this thing pretty mercilessly and I'd like for the transmission to be able to take it for over 100k miles before needing to get back into it.

I guess what this post all comes down to is, how much beefing up does an 80E need? I'd like to do this and be done so I can move on to my car and other things.

Thanks in advance for any input.

Best,

Jared

rated for 650 ft. lbs. and I like the price, but B&M scares me....
https://www.summitracing.com/parts/bmm-118002/overview/

these guys have some pretty nice looking stuff but can get pretty pricey when you +core +shipping +hardened input shaft....
http://www.finishlinetrans.com/transmissions/index.htm

These guys have a great internet reputation but ghastly expensive....
http://www.jakesperformance.com/4l80/

These guys are out there but I've read/heard bad things....
https://www.monstertransmission.com/4L80E-Transmission_c_3936.html

 

[bob64]

Wow! I thought prices for transmission are high up here.

When thinking 4L80E think Th400 with extra gear.

I got a built BBC with 2-250 shots nitrous and the 4L80E and its still holding. Is it built, a little but nothing crazy and l got it for $1800.

You can buy a rebuilt 4L60E/65E for $900 plus exchange and a 4L80E for $1100 here in Ontario. Maybe try taking your 4L65E to a rebuild shop and exchange with an upgrade to 80E?

I have 3 4L60E, Cutlass 400 hp plus, Denali 320 hp and Escalade 320hp and never had an issue but l have hear horror stories about them.

Edit, forgot the Suburban has a 4L60E 325,000kms and mostly pulls trailers and no issue.

 

[87National]

If it were my truck......
Good used 4l80e $500
Transgo hd2 kit $100
Circle d torque converter $600
big transmission cooler $100
shorten driveshaft $150

 

[Tomeal]

How bout an Allison?

 

[olds307 and 403]

The 4L60-70E sucks, especially the 3-4 clutch pack. Your launch will suffer with a 2.48 first gear vs a 3.06 first gear. Supposedly a 4L80E is good for 600+ hp with just a boost in line pressure.

 

[Northernregal]

If it were my truck......
Good used 4l80e $500
Transgo hd2 kit $100
Circle d torque converter $600
big transmission cooler $100
shorten driveshaft $150

Even this is overbuilt but I 100% agree. Stock junkyard runner with an HD2 shift kit will live in a 600whp 3800lb street car. My car build is a used stock gm rebuild with a shift kit and a converter. You need to swap 2 wires in the trans harness and it will pretty much bolt in with a sector swap on your tune and a junkyard driveshaft.

 

[L92 OLDS]

Opinions Wanted! How strong is a stock 4L80E?

The GM rating is 885 ft. lbs input torque on the 4l80E as to the GM rating of 670 ft. lbs. for the 4l60E. I found a 2009 low mileage 4L80E on Car-Part.com and bought one from a Detroit salvage yard for $500. It came in an Express van which seem to be good candidates for 2wd applications. Most of the prices you see published on Car-Part.com are negotiable. I took it apart with a friend in the transmission business and we installed the Transgo HD2 kit. I didn't know what to expect when taking it apart but it showed little to no signs of wear. I could have left it alone and been OK. In stock form many say they re good for 6-700 HP and with the HD kit they say I have read claims of 1000 or more and Trans go claims they will hold "BIG POWER" he he. I have a good used, low mileage 2004 4L60E for sale if your interested (4x4). Personally I would go for the 80E. Your quoted prices sound really high....You don't have to buy local. I found that 2x4 4L80's are usually cheaper. Hopefully that works in your favor. Good luck brother!

http://www.car-part.com/

http://rover.ebay.com/rover/1/711-5...0001&campid=5335822911&icep_item=113471709609

 

[Injectedcutty]

Jared, I'd go with the 80E also. Obviously I got mine as a good unit from an Express and just put the HD2 kit in it. The converter was the dinger, but for the intended use this trans should do just fine.

I had a really good local shop that does alot of racing stuff quote me a build on mine, they said $2500 with my core and it would be good for 1,400HP+.

 

[motorheadmike]

Just put a good low mileage used 80E in there with a shift kit and call it a day. The stock flexplate with work with either an LS-style converter or an adapter bushing. Get at least a 3600 stall converter - FTI or Circle D seem like the way to go. Driveshaft is the same length, you just need a new slip yoke - Sonnax has a nice one. Last part is an adapter harness from the 60E to 80E.

 

[olds307 and 403]

GM wishes the the 4L60E could take 670 ft/lbs, cut it in half maybe. Also remember you go from a .70 to a .75 overdrive. I assume your truck has tall tires. The 4L80E is a strong trans but the ratios are not ideal at all in my opinion.