What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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iamdub

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How often do you have to renew the plates/registration?

Every two years. I pay it online and they mail me a new registration with a sticker. I peel it off and stick it over the old one on the plate.


Here is every 2 years, and you have to have a recent (within 30 days) inspection in the system if renewing online or paper if in person. Also have to have the past 2 years of personal property taxes paid which they look up in their system.

Thankfully, these things are all separated functions here... Currently.


The only problem I have with not being current in the system is my insurance can't track my mileage. Since I drive a company vehicle daily for work, I qualify to have my Tahoe under the cheaper "low mileage/pleasure vehicle" status as long as I remain under 7,500 miles annually. They rely on the report from the inspection station to monitor the mileage. Without it, they automatically raise me to the daily commuter rate. I just stop by the office and let 'em look at my odometer every year.

Your questioning just prompted me to check my mileage since I'm due to stop by State Farm. The most relevant documentation I have is a pic of my odometer I took when I got home from my trip to Florida on November 17 of last year. I've driven it 5,459 miles in 12.75 months.
 
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YuCanada

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looks nice..

Get the torque app and test the hybrid battery yourself. most shops have no hands on experience with these trucks and tell owners all kinds of stuff. the battery is the only true wear item of the hybrid system. so saying the hybrid system is toast means they don't understand how anything works.

but honestly the battery is probably showing it's age, heck it's probably had some battery work to make it this far. the thing about the battery is technically as long as it's strong enough to crank the engine over, it will run. but it's very ******* the whole driveline when they start surging and bucking coming in and out of auto stop. at some point they get so bad the poor thing starts revving the engine trying to keep itself running and if you're driving people say it's had to stop them, they wanna push thru the brakes. I haven't felt that, but mine did set a battery code about 140k and the battery cells were pretty bad. not enough to leave you stranded but enough it needed replaced. I went the more untested lithium upgrade route.

there's a bunch of different options to rebuild, referb it or replace. all much cheaper than rebuilding the standard 6 speed tranny the non hybrid has which eat themselves in stock form oddly at the about same rate. so it's a wash.

if starts doing funny stuff you drive it in M4 mode, it won't go into auto stop mode, which helps when the battery is weak. Just hurts fuel mileage and has a little less overdrive ratio on the interstate. Just take care of that tranny. they are getting hard to find used, almost no shop knows how to rebuild them, even thou parts are listed.
Hey I appreciate this info! These were so unpopular that it is hard to find these kinda of details.

This is what I assumed too, the HV battery is bad enough to cause weird issues and throw codes once in a while, but good enough to start the truck as from my understanding the HV battery powers the transmission motor that starts the truck.

Currently auto stop doesn't work, it does the weird bucking when going slow at stop sign traffic. Seems to brake the same and accelerate as slowly as it used to when I had it last in 2016. It has a very hard time starting, is that because the HV battery is too weak to spin the engine fast enough? Took me 10 tries to start yesterday and had to give some gas. Again I would assume cold transmission fluid would add resistance and make it even harder?

So this thing likely just needs the HV battery replaced, but my SIL has spent enough on it since 2016 and just wants to get rid of it. This will be good info to pass onto whoever buys it
 

j91z28d1

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Hey I appreciate this info! These were so unpopular that it is hard to find these kinda of details.

This is what I assumed too, the HV battery is bad enough to cause weird issues and throw codes once in a while, but good enough to start the truck as from my understanding the HV battery powers the transmission motor that starts the truck.

Currently auto stop doesn't work, it does the weird bucking when going slow at stop sign traffic. Seems to brake the same and accelerate as slowly as it used to when I had it last in 2016. It has a very hard time starting, is that because the HV battery is too weak to spin the engine fast enough? Took me 10 tries to start yesterday and had to give some gas. Again I would assume cold transmission fluid would add resistance and make it even harder?

So this thing likely just needs the HV battery replaced, but my SIL has spent enough on it since 2016 and just wants to get rid of it. This will be good info to pass onto whoever buys it


yeah. most like the battery is bad.. like really bad and will leave it dead in the water at some point. and it's a bit of a hassle to jump start them. you need a high end scanner to put it into a mode that will charge the the hybrid battery thru the 12v battery with a 20plus amp charger on it. that is if the hybrid battery will even take a charge at that point.

you're in Canada, so I've heard shipping is a hassle so it's better you use a Canada based company. look for the ones that replace prius batteries. it's basically the same thing. most people here use a company called greenbean. cheap referbed batteries. they will come to your house and swap it out. it used to be about 2500$ with a warranty. but prices are crazy. so I don't know that is now. there's also a DIY using wrecked prius cells off ebay, guys do that for cheap too. that takes some time thou. you gotta buy 2 packs, cycle them all on a load bank and charger a few times and then pick 40 of the best cells, balance charge then and then install. but its a hassle unless you're into that sort of electrical stuff as a hobby.

I went with the new diy cells routh from Nexcell. they are drop in replacement using lifepo4 cells instead of the old school tech. but there is come creditable arguments about if it's the best bang for the buck and untested longevity, so as much as I'm enjoying mine and see no sign of decline, I always hesitate to recommend them unless you're interested in that sort of thing and have spare cash.

sadly that's basically how these all ended up in the junkyard.. zero dealer level training even when new, so they couldn't fix them in a timely manner, all the same afm lifter issues of the non hybrid ones and they just bleed people dry trying to keep them running. when truth is the hybrid battery didn't make it the full 8 year battery warranty, gm just loosened the parameters which set off the code so they didn't have to cover it.

interesting tech, but ahead of the time battery chemistry by a good 20 years. we are just now seeing Toyota hybrid trucks and stuff for a reason.

I'm not really a fan of all electric cars but I do think hybrids and especially plug in hybrids make for useful city cars as long as they are easily repaired.

if you haven't seen it, there's a thread in the hybrid section about using the 5$ torque app and a 20$ dongle to read the cell voltages and see for yourself if it's bad. Basically the voltage should all be within 0.02 volts while under a load, when I changed mine out most would be 17v and a few drop. to 8v while trying to. move the truck and crank coming out of auto stop. long dead. it's got the pids for a few other things to monitor too, like battery Temps, amps into and out of the battery. cooling fan speed any useful still.
also there's a section for these trucks on a mainly prius board that is very useful too. can log the data and one guy's will graph it all out and stuff.

i know it's had to come off the money for it thou, since unless you've done all the afm fixes and other stuff. it's a bit of a time bomb anyways. probably due for a lot of the standard trucks mechanical repairs by now too.
 

alpha_omega

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How often do you have to renew the plates/registration?

Here is every 2 years, and you have to have a recent (within 30 days) inspection in the system if renewing online or paper if in person. Also have to have the past 2 years of personal property taxes paid which they look up in their system.
Michigan requires no inspection (otherwise 60% of the vehicles would probably fail due to the rust belt winters and pothole filled back roads) and my plate/reg has no expiration (100% service connected disabled vet). Otherwise it’s every two (?) years? It used to be annual, but they got lenient during COVID and realized the SoS/DMV it’s a racket. Now most of the stuff can be completed online, unless you need a title transfer or new drivers license.
One thing they did change to prevent people from pulling an @Tonyrodz job on one another, is the license plate tags now have the VIN on them in small letters. Easier for the cops to check if the tag matches the plate and registration for that specific vehicle.

Luckily for me even when I lived in other states, by having the vehicle registered in Michigan I didn’t have to adhere to the inspection laws of that state.
 

justchecking

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On the road again. Appears I have increased my gas mileage 20-25% while towing the camper. Normally I just leave it in Tow/Haul where it usually stays in M5 and rarely M4. I saw a post from @NickTransmissions to use M4 and M3. It always seemed like it was lugging in M5 pulling my 5000LB square camper. I manually put it in M4 now and M3 up hills. Fuel mileage went from 8+ to 10+ (depends on weather etc). More testing needed however.
View attachment 413454
Well! Most recent trip manually limiting to M4 or M3 because M5 at 65 MPH seems to lug the motor was not what I expected. 284 miles required 38.9gallons or 7.3MPG. It was pretty windy.
 

Fless

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Walmart. Everstart maxx. Same battery as the parts stores and the ac delco it shipped with. Much cheaper and same warranty

^^This especially if you can get it in the Maxx version. The lower version is also okay, especially considering the availability of zillions of locations for warranty purposes. I recently replaced the 96R in my Fusion for ~$117 (after core) with an EverStart Plus and that has a 2-year replacement warranty. I'd have bought the Maxx (3-yr replacement) if it would have been offered in that size.
 
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