I need some gearhead advice. I have a 2012 Burb with the 6L80 that has 202k miles. I was towing my boat (20ft Ranger fiberglass) and lost 3,4,5,6 gears. What would be my best route going forward in y'alls opinion? Motor runs good. Are these trannys worth rebuilding? Should I use different parts to rebuild? I have no idea about this stuff so any advice is greatly appreciated. Trying to decide if I should go cheap and sell it or rebuild it good and keep on truckin'. Thanks!
HELP! 2012 suburban 6L80 trans failure
- Thread starter neffcd
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strutaeng
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Please read through this thread:
www.tahoeyukonforum.com
Are you thinking of rebuilding it yourself? Have you rebuilt transmissions before? Is this your primary use vehicle?
GM 6L80 Transmission Information Thread
Hi All, Since so many of us own at least one Tahoe or Yukon equipped with a 6L80, I figured I'd start an all-encompassing transmission thread with videos, links and other information as it relates to the 6L80/90 transmissions. I'll get it going with a tear down and inspection video and go from...
www.tahoeyukonforum.com
Are you thinking of rebuilding it yourself? Have you rebuilt transmissions before? Is this your primary use vehicle?
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Let's hear directly from our resident transmission expert for this thoughts and perspectives.
@NickTransmissions
@NickTransmissions
Does reverse work?
Yes and 1st and 2nd.
Sounds like you lost your 4-5-6 clutch completely and the 3-5-R clutch is on its way out (there's nearly twice as much line pressure avail in reverse at the point of engagement unless you're shifting at WOT into 3rd or 5th so you often still have reverse even when 3rd/5th are no longer functioning. The 3-5-R clutch is on/applied in 3rd, 5th and reverse....The low reverse clutch and 3-5-R clutch are on in reverse. Your 1-2-3-4 clutch is still operable as is your 2-6 clutch but the other two forward shifting clutch packs are shot.
You planning on rebuilding the transmission yourself?
You planning on rebuilding the transmission yourself?
blackelky
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That gives me hope for some more miles before mine goes my tahoe is at 98k
petethepug
Michael
Good question and smart of you to be open to all options. First off, the difference between a total cut rate and maybe questionable trans rebuild would be -$1.5k. So figure you’re looking at that dollar amount up in the air after you take all your time to fix it.
With GM fighting for the strike of their life, it’s probably not a good time to upgrade as the parts warehouses are on strike too. The one in San Diego just went to 24/7 picket lines.
You could make good resale on selling private party as well as a trade, but keep in mind, unless you got a smoking deal on your 1st pick, hope too, always wanted truck, you’d still lose a little equity because new / used vehicle sales are high right now.
When our trans was hinting with a very occasional 2-3 slip on our 08 YXL Denali, we did find our dream truck at a TX Lexus Dlr and drove it back to CA. It gave us time to have a dealership pro Resto the paint & interior and sell it for $1.5k less that what we got our 09 Esky Plat ESV AWD for.
Three years after owning the Esky, the trans went out. I couldn’t be happier because I fully intended on keeping the truck. If you find your dream truck, buy it outright and then sell / fix the Burb when all the pressure’s off.
Do both. Shop for a trans rebuild as well as your dream truck. Keep in mind your Burb is likely due for the items I listed in another thread that are about 1-$1.5k if you buy them off R/A and have the shop install ur parts. Those same parts are 2-3x more in labor and cost is the shop sources them and the trans is not out.
I spent $6.5k for a hand rebuilt trans and all those parts, so I’m good from the 175k I’m at now til 275k clicks later.
With GM fighting for the strike of their life, it’s probably not a good time to upgrade as the parts warehouses are on strike too. The one in San Diego just went to 24/7 picket lines.
You could make good resale on selling private party as well as a trade, but keep in mind, unless you got a smoking deal on your 1st pick, hope too, always wanted truck, you’d still lose a little equity because new / used vehicle sales are high right now.
When our trans was hinting with a very occasional 2-3 slip on our 08 YXL Denali, we did find our dream truck at a TX Lexus Dlr and drove it back to CA. It gave us time to have a dealership pro Resto the paint & interior and sell it for $1.5k less that what we got our 09 Esky Plat ESV AWD for.
Three years after owning the Esky, the trans went out. I couldn’t be happier because I fully intended on keeping the truck. If you find your dream truck, buy it outright and then sell / fix the Burb when all the pressure’s off.
Do both. Shop for a trans rebuild as well as your dream truck. Keep in mind your Burb is likely due for the items I listed in another thread that are about 1-$1.5k if you buy them off R/A and have the shop install ur parts. Those same parts are 2-3x more in labor and cost is the shop sources them and the trans is not out.
I spent $6.5k for a hand rebuilt trans and all those parts, so I’m good from the 175k I’m at now til 275k clicks later.
solli5pack
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Just curious. Is rebuilding a transmission at home a legit option for a d.i.y'er?
Based on Nick's analysis, I would say yes it is worth it to rebuild the 6L80. Aside from the torque converter slip problems (which is more software than mechanical), the most likely mechanical design flaw is the undersized 4-5-6 clutch. So if 4-5-6 is gone and 3-5-R is not far behind, you trans is easily re-buildable with standard consumables.
200K for a 6L80 that tows is a very good life. If the truck is worth $10K good condition running, it is worth maybe $5k with a bad transmission, and probably very little for trade-in at 200K regardless of the trans. So with a quality trans rebuild costing $5-6K, it is your best option to 'buy' another 100K miles plus some extra for other maintenance from a pure dollar per mile stand point.
If you just want a new truck, then a new Suburban with a 10-speed is a very nice option, but you will not get your trans rebuild cost back on trade-in. So in that case rebuilding the trans is not a good idea. Someone may happily give you $4k as-is on a private sale with a bad trans, and trade-in might be $6k with a new $6k rebuilt trans.
200K for a 6L80 that tows is a very good life. If the truck is worth $10K good condition running, it is worth maybe $5k with a bad transmission, and probably very little for trade-in at 200K regardless of the trans. So with a quality trans rebuild costing $5-6K, it is your best option to 'buy' another 100K miles plus some extra for other maintenance from a pure dollar per mile stand point.
If you just want a new truck, then a new Suburban with a 10-speed is a very nice option, but you will not get your trans rebuild cost back on trade-in. So in that case rebuilding the trans is not a good idea. Someone may happily give you $4k as-is on a private sale with a bad trans, and trade-in might be $6k with a new $6k rebuilt trans.
I would say yes, it is an option.
The 6L80 is pretty straightforward, and parts are readily available for a reasonable price given the mass quantity of transmissions on the road.
The main requirements are a good transmissions jack, large snap ring pliers ($75), pump centering tool ($150), the rest is mostly standard tools( if you have things like a straight edge, dial calipers, feeler gauges, snap ring pliers, a brass drift, some pick tools and seal/bushing installers). You can probably get by without the pump alignment tool by using some special bolts or just not aligning at all. You can make a rudimentary clutch press with threaded rod and some metal pieces if you don't have a press.
If you have never done a transmission or never plan to do one again, there are plenty of pros than can do a quality rebuilt in their sleep on a 6L80, for very reasonable labor cost, so it really isn't worth your time. However if you are intent on learning and DIY, it is an option.
petethepug
Michael
Doing a trans yourself is something that’s hands on and a learning process. It’s just really cool to understand and see what makes it tick. The only downside is if you miss something, it requires undoing everything then redoing it with replacement $ parts and the downtime, if you have it.
The Transmission is great, and it is way cheaper to get it Rebuilt than buy a new car, or someone else's Problems. I put a new Long block in from Rockauto and had my transmission replaced with a rebuilt and I am going on 260K now No Leaks and very reliable. I still have the original AC Compressor, but may soon need to replace the Clutch.
Best Regards
Bob D
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I lost my tranny in my 07 Escalade, 6L80 trans. It started going into limp mode or neutral on the 3-4 shift, usually when towing or accelerating hard. I was told it was a mechanical failure by a tranny shop so I pulled it out, had it rebuilt, Trans Star parts, all new drum and clutches with upgrades. Put it back in and had the exact same issues? The rebuilt trans was given back to me with the exact Tehcm from my failed tranny. It was an upgrade option to replace but the shop told me the Tehcm was not my problem. They were wrong. I installed a new Tehcm, actually rebuilt by a shop in Florida that did a great job on the rebuild, programmed it, offered great advice before and after install and now my tranny works fine again. I should have installed a new Tehcm prior to the rebuild. The car has 175K on it so at least now I know it has a solid transmission in there. I guess my point is, this is a very nice tranny, a rebuild gives you a 100% life again if done correctly but plan on installing a new Tehcm or rebuilt and of course a brand new torque converter as they tend to fail also.
As far as rebuilding a 6L80 myself, I have been ASE certified in Engine Performance, Engine Repair and all 5 areas of engine rebuilding so Gold Certified. I went to a guy with 30 years experience and had him rebuild my tranny. I know it is just parts but parts I have no experience with tranny parts. An experienced guy will look and know based on the wear he sees if a part is good or bad or if something has not been functioning correctly. These trannys and transfer cases are heavy and a chore to remove and then install. Not a job for a person not familiar with his tools, jacks etc to do this and not cause problems.
I think my tranny rebuild with new drum, torque converter and Tehcm rebuild and program was under $3500 and I did the R&R. Would have been much faster and far less trouble if I had installed the rebuilt Tehcm at the same time as the tranny. Mark
As far as rebuilding a 6L80 myself, I have been ASE certified in Engine Performance, Engine Repair and all 5 areas of engine rebuilding so Gold Certified. I went to a guy with 30 years experience and had him rebuild my tranny. I know it is just parts but parts I have no experience with tranny parts. An experienced guy will look and know based on the wear he sees if a part is good or bad or if something has not been functioning correctly. These trannys and transfer cases are heavy and a chore to remove and then install. Not a job for a person not familiar with his tools, jacks etc to do this and not cause problems.
I think my tranny rebuild with new drum, torque converter and Tehcm rebuild and program was under $3500 and I did the R&R. Would have been much faster and far less trouble if I had installed the rebuilt Tehcm at the same time as the tranny. Mark
Yep. I always replace the TEHCM, IMS and Harness/speed sensors when going through a 6L unit. Glad you go yours sorted out...
