[jmbrad]

Am I the only one that feels this way?

I drove a 98 for 13 years with no issues. 250,000 miles, not a single problem except water pump, starter, and wear items. Drove another GMT400, the last year you could get one, 1999 for another 7 years. No issue except the brakes. Lousy brakes on the regular half tons. The 98 was a heavy half ton with the 3/4 ton rear end. If I could clone that truck I would do it until I die.

Transmission went out in my 2011 Sierra today. Only 69k miles. I've only owned it since Dec 2020, less than 2 years. Between the flex fuel nonsense and having to drive it 10 miles after you fill up when I only work 8 miles from home and now this load of crap with the transmission, I'm done with GM trucks from this century.

I'm I alone in my sentiment?

 

[19trax95]

The older trucks definitely stand the test of time way better.

The square bodies and the GMT400 trucks are the most solid trucks GM has ever built in my opinion. And they will be around forever.

The GMT800s are also pretty solid and reliable trucks.

Once you get to the GMT900s, the quality dropped WAY off. I'm not a fan of the 900 trucks at all.

GM stepped up their game big time for the k2xx trucks as far as build quality and materials go.

Biggest downfall of the older trucks is they lack capability compared to the new ones. The frames are way stronger, suspension much beefier, and motors way more powerful in the new compared to old.

What happened with you flex fuel? Alcohol composition sensor drifted high?

 

[jmbrad]

What happened with you flex fuel? Alcohol composition sensor drifted high?

Yes. Before I knew what was happening, I changed the fuel pump, like all GMT400 trucks I had before the GMT900. That's one of the issues I forgot about. I did have to change the fuel pump in the 98. Never did in the 99.

Anyway, the fuel pump change didn't fix the hard start issue, so started searching the forums. Yes, was consistently reading high regardless of what fuel I used. After a fuel trim and ethanol reset at the dealer that cost me 140.00, I've been anal about only filling up with a warm engine and driving at least 10 miles while monitoring the ethanol content. I hate it, but I've been tolerating it because of the cost of used trucks right now.

And because I live in NC, I'm part of the current LC9 class action lawsuit. Would be nice to get a buyback. I had planned on keeping it long enough to see how the lawsuit turned out.

 

[swathdiver]

@jmbrad How old are your O2 sensors and are the GM OE?

You think you're going to get anything meaningful from that lawsuit? You'll be lucky to get a check for $4.31 while the vultures put their kids through college and vacation in Europe.

 

[jmbrad]

@jmbrad How old are your O2 sensors and are the GM OE?

You think you're going to get anything meaningful from that lawsuit? You'll be lucky to get a check for $4.31 while the vultures put their kids through college and vacation in Europe.

O2 sensors, I assume, are original. They pulse like they're supposed to when I was diagnosing the issue earlier. I am aware the fuel composition sensor is virtual and based off O2 calculations.

I have been part of class action suits before, and yes typically only the "liars" win. However, I have also gotten significant awards too. MFS lawsuit I got over 800.00 from. This LC9 suit only includes a few "bellwether" states, of which NC is one. I'm not holding my breath by any means, but I was planning on keeping the truck until the outcome at least.

My dad passed away in March and I had 3 trucks until 2 weeks ago. Sold his 77 Chevy K10 and 08 Nissan frontier. I didn't expect the transmission in my truck to crap out on me so soon. Story of my life.

 

[swathdiver]

O2 sensors, I assume, are original. They pulse like they're supposed to when I was diagnosing the issue earlier. I am aware the fuel composition sensor is virtual and based off O2 calculations.

I have been part of class action suits before, and yes typically only the "liars" win. However, I have also gotten significant awards too. MFS lawsuit I got over 800.00 from. This LC9 suit only includes a few "bellwether" states, of which NC is one. I'm not holding my breath by any means, but I was planning on keeping the truck until the outcome at least.

My dad passed away in March and I had 3 trucks until 2 weeks ago. Sold his 77 Chevy K10 and 08 Nissan frontier. I didn't expect the transmission in my truck to crap out on me so soon. Story of my life.

A lot of guys say to change out the O2 sensors every 100K miles. I kept mine into the 160s and realized that she too started having trouble calculating the alcohol content properly. New sensors fixed that. Mine weren't lazy, no codes, just old enough that they started having trouble doing math!

Intake and exhaust leaks can also cause the readings to skew. Sorry to hear about the transmission, many of them with regular service run into the 200s before requiring overhaul.

 

[jmbrad]

A lot of guys say to change out the O2 sensors every 100K miles. I kept mine into the 160s and realized that she too started having trouble calculating the alcohol content properly. New sensors fixed that. Mine weren't lazy, no codes, just old enough that they started having trouble doing math!

Intake and exhaust leaks can also cause the readings to skew. Sorry to hear about the transmission, many of them with regular service run into the 200s before requiring overhaul.

Mine only has 69k, but only the last 11k are mine since Dec 2020. So I can only assume someone must have dogged it before I bought it. I'm really easy on stuff. Only transmission issues I've ever had from vehicles were Fords. A 74 LTD and a 96 Sable. Twice on the LTD.

Hind sight is 20/20. I should have listened to my Dad more often. Now he's gone.

 

[swathdiver]

Mine only has 69k, but only the last 11k are mine since Dec 2020. So I can only assume someone must have dogged it before I bought it. I'm really easy on stuff. Only transmission issues I've ever had from vehicles were Fords. A 74 LTD and a 96 Sable. Twice on the LTD.

Hind sight is 20/20. I should have listened to my Dad more often. Now he's gone.

Part of our nature, to think we know more than those who came before us! Cherish the memories and consider putting them to paper.

 

[Sperry]

Only 69k miles.

A trusted shop local to me swears by the 4L60E 4-speed. His rebuild price is $2,850 with warranty. Since you do not know the history, maybe trusting the truck rather than the previous owner?

I've got the same GMT902. A contractor tried talking me into towing far over the 4700 lb rating, telling me "The truck can take it". Yeah, I said, no way. You never know. Someone may have hooked 6,000 lbs to the truck for a while and wore out a few critical components. The transmission itself should easily last 200k-300k, even 500k+.

 

[Chevy-SS]

Am I the only one that feels this way?............. I drove a 98 for 13 years with no issues. 250,000 miles, not a single problem except water pump, starter, and wear items. ..... 1999 for another 7 years. No issue except the brakes. Lousy brakes on the regular half tons. The 98 was a heavy half ton with the 3/4 ton rear end. If I could clone that truck I would do it until I die..................Am I alone in my sentiment?

Brutha, you are not alone in that sentiment. Just prior to COVID, I spent about 6 months shopping for a brand new (or low-mileage, gently used) GMC or Silverado 1500 4WD. I am a picky buyer, I was looking for that 'special' truck that really grabbed me, something I could appreciate every little detail in. And I have to say, I didn't find it, I was disappointed in many different things........... not gonna try to list them here.

Anyway, I ended up keeping my '03 Silverado, still driving her and still love her. 128k miles now and runs like new. I've got Bluetooth, a great stereo, TPMS, a nice interior, great ride quality, and she's very easy to fix, plus she costs me nothing now (except repairs). And if she gets a little chip or ding, it's no big deal.... worry-free.

Like you, I also had a '98 K1500, with 5.7L and it was a terrific truck, with shitty brakes. I should have upgraded the wheels and brakes, but never did. But man, that truck ran great. But my fav is this '03 I now have. I would keep this truck til I die, if it would last. And I think it might, except for the rust, that's gonna kill it. If/when I have to replace her, I might look for another of this gen, from rust-free zone, with low miles.

 

[jmbrad]

So far estimates range from 3800.00 - 4504.00 for either a rebuild with upgrades or, the highest, a remanufactured from unknown source. Shop wouldn't tell me.

I'm friends with one shop owner about an hour away, he was also the middle price, 3900.00. I guess that's the best option for me. He replaces the computer and valve body regardless of condition just on the safe side and said he uses borgWarner parts.

Sounds good? Opinions?

Closed the week of the 4th, can start on it the following week.

 

[Chevy-SS]

I like the deal with your buddy at $3900. Maybe he can tweak the tranny shifts a little. I had a 2011 Chevy Avalanche that I bought new, and the shifting was just horrible. It was set from the factory to shift early in all gears (to save gas, I guess), and it would ALWAYS be in a gear that was too high for the speed, except for highway, so it was lugging all the time. This, coupled with the atrocious AFM, made for the worst-driving vehicle I had ever owned, LOL. I had it re-tuned (both the engine & trans, with AFM turned off), with all the shift points raised, and it was MUUUUCCCH better and more pleasant to drive.

 

[Sperry]

I like the deal with your buddy at $3900

Just looked it up. My quote dates from August 5th 2021 . . .

 

[jmbrad]

I like the deal with your buddy at $3900. Maybe he can tweak the tranny shifts a little. I had a 2011 Chevy Avalanche that I bought new, and the shifting was just horrible. It was set from the factory to shift early in all gears (to save gas, I guess), and it would ALWAYS be in a gear that was too high for the speed, except for highway, so it was lugging all the time. This, coupled with the atrocious AFM, made for the worst-driving vehicle I had ever owned, LOL. I had it re-tuned (both the engine & trans, with AFM turned off), with all the shift points raised, and it was MUUUUCCCH better and more pleasant to drive.

Yes sir, couldn't agree more with the shift points being weird. I have the 3.08 gearing to make matters worse. Always felt like I was lugging the engine too.

I'll ask if he can do a custom tune along with the programming. I took care of the AFM with a Range plug in device since the first month of ownership. It's a little inconvenient, but quick and dirty "fix".

I can say this much about my engine: my LC9 must be one of the good ones. No oil consumption at all. Regardless of whether I use the Range AFM delete or not. I know many have not been so fortunate.

It will be a couple weeks before I get the truck to the shop. They're closed next week and booked up until the holiday.

Question: Should I spring for the billet parts? I plan on towing a couples coach, 4000lb dry weight max, at some point in the future. Max tow rating on my truck is 6800 lbs with a payload of 1788 (IIRC).

 

[jmbrad]

Taking my truck to the transmission shop tomorrow. Hopefully not as bad as they expect.

 

[RedSLEd]

Keep us posted.

 

[jmbrad]

Got the truck back yesterday. Unfortunately I'm not happy with the way it drives. Feels like it's still too soft in the shifts like it was when I bought it, but before the slipping started.

They changed out all the valves, the computer and the torque converter. All parts are supposedly longer lasting. They also put in a larger transmission cooler. Total because of the larger cooler was $4494.00

I'm sick to my stomach over it.

I've been reading up a lot on the 6L80E and it really doesn't matter what you do to it it's still drives like crap. It will never shift like a 4L80E no matter what you do to it.

I'm ready to just give up on trucks all together. At this point I want to sell it and get an old GMT400 2500 Suburban or Yukon.

 

[RedSLEd]

You can GREATLY improve the way the 6L80 feels and shifts with a good tune. I love mine. Maybe get with Lew...

DiabLew Tune - Custom Tuning for GM Vehicles - DiabloSport inTune 2030, Diablo inTune 8245 Platinum, DiabloSport Trinity, inTune, DiabloSport Trinity 9245 Platinum, Custom Tuning by 06MonteSS, custom GM tuning

DiabLew Tune - Custom Tuning for GM Vehicles - Diablosport inTune, Diablosport Trinity, diablo inTune 2030, diablo inTune 8245, 06MonteSS custom tuning, diablo custom GM tuning

www.diablocustomtune.com

 

[Chevy-SS]

Yeah, this ^^^^^^^^^^ trannies are extremely tunable nowadays. They respond wonderfully to a good tune. I bought a brand new 2011 Avalanche with 6L80E & 5.3L... it shifted horribly, was sluggish all the time (especially with the AFM), it would shift into high gear at ~30mph, and then refuse to downshift until you REALLY pressed on the go-pedal. It was very disappointing, and I too was "sick to my stomach" that I bought this new vehicle that I now (after about 2 days of ownership) hated driving, haha.

Luckily, I have a terrific GM expert tuner in my area, so I took the truck to him, and he tuned the engine and trans, and it drove beautifully after that. It took him as long to tune the trans as it did the engine. I was in the vehicle the whole time, and I was amazed at all the tuning options for the trans................

 

[jmbrad]

You can GREATLY improve the way the 6L80 feels and shifts with a good tune. I love mine. Maybe get with Lew...

DiabLew Tune - Custom Tuning for GM Vehicles - DiabloSport inTune 2030, Diablo inTune 8245 Platinum, DiabloSport Trinity, inTune, DiabloSport Trinity 9245 Platinum, Custom Tuning by 06MonteSS, custom GM tuning

DiabLew Tune - Custom Tuning for GM Vehicles - Diablosport inTune, Diablosport Trinity, diablo inTune 2030, diablo inTune 8245, 06MonteSS custom tuning, diablo custom GM tuning

www.diablocustomtune.com

Yeah, this ^^^^^^^^^^ trannies are extremely tunable nowadays. They respond wonderfully to a good tune. I bought a brand new 2011 Avalanche with 6L80E & 5.3L... it shifted horribly, was sluggish all the time (especially with the AFM), it would shift into high gear at ~30mph, and then refuse to downshift until you REALLY pressed on the go-pedal. It was very disappointing, and I too was "sick to my stomach" that I bought this new vehicle that I now (after about 2 days of ownership) hated driving, haha.

Luckily, I have a terrific GM expert tuner in my area, so I took the truck to him, and he tuned the engine and trans, and it drove beautifully after that. It took him as long to tune the trans as it did the engine. I was in the vehicle the whole time, and I was amazed at all the tuning options for the trans................

Thank you for the encouragement. I've exchanged emails with Lew before. He said when I got the transmission fixed to get back with him.

I really don't want to throw any more money at it. Cut my losses and get out.