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Best Choice for Transmission for 04 Z66

ErieNortheastern

New Member
Joined
Mar 8, 2022
Messages
4
Location
Augusta GA
Just joined today I am having a problem. Bought a 04 avalanche in June of 2021 a Z66 in grey for $5800. Had some issues replaced ABS computer AC pulley belt and tensoner. Had its cluster replace by another one odometer shows 155K carfax says over 250K should be on it new touchscreen radio and audio systems also. Rear main seal and gasket after it just hemorrhaged oil at my jobsite on top of new intake gaskets and main belt tensoner and belt plus sensors. Febuary had to shop it again for a window regulator and motor and idler pulley along with a water pump. Last week the rebuilt trans blew on me and now I need a new transmission as the one it has the housing is cracked.
I've been trying to find a trustworthy place that will stand behind what they ship so far I've got the brands in mind:
Level 10 $4100 for the Bulletproof 4L60e
Hughes Performance $5500 for 4L60E tried to put me in a 4L80E at $4500
Monster transmission & performance
JEGS
Jasper's
Weeks Trans local place near me using ETE remans
Cheeseboroughs (they want to reuse my old trans the internally failed with a cracked casing and stillwant to use parts from it in my new trans)


Any advice would be helpful.
 
Welcome aboard! -and- Sorry to hear about all your woes, but the glass half full angle is: Hopefully now that you've replaced all these parts, you'll get to enjoy one of the best parts of owning an Av; driving it.

I'm not a transmission pro by any means, but I have destroyed 4 of them in my life.

The 1st I went with a mom and pop shop and had mine re-built. To the best of my knowledge theres nothing wrong with using parts out of the old transmission, as long as they not damaged! It saves money. Cheap and Had no issues.
The 2nd I went with a regional (Northern WV-Western PA) Tranmission specialty shop- came with 6mos 6,000 mi warranty. Lasted about 40,000 hard miles moderate price took some abuse.
The 3rd time I used the Ford Dealer I worked for in Dallas. Expensive but coast to coast 2yr 24k warranty. Sometimes piece of mind is worth a little more?

THOSE WERE ALL FORD EXPLORERS which was too heavy for its smallish drivetrain

The 4th time was a '91 Honda Accord I used as work car. And I also cracked the housing. Used AAMCO- was fairly priced and had coast to coast 3yr/36 warranty. It was still goin when I sold it 90,000mi later.

You may get mixed opinions on this but, I think the weakest part/poorest design of my 2011 with the 6L80 is the Torque Converter. Mine is going out now. When it goes it takes the trans, lines, cooler, and all with it. Don't believe the 4L60, e , and 80 had the same issue?

I recommend upgrading a few parts while your in there. It's not much more money but will help instill some confidence that it'll last, and be able to handle your heavyweight truck.

I spent 4-5 days 3 weeks ago emailing back and forth with a sales tech at https://www.sonnax.com/ . They diagnose and redesign a lot of the flaws out of oe transmissions/parts. Also have a stellar reputation for quality....and have spent a long time making chevy transmisssions better. Couldn't hurt to at least reach out and ask what they recommend.
The only thing else know to suggest is a crate trans from JEGS or SummitRacing.

The more you source and procure yourself the more money youll save, the more you'll learn, and the less likely you;ll get shafted
Good luck
 
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