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

[Sparksalot]

If I had it to do over again, I would leave the factory external cooler in place and just add the 700w fans from the K5L package to keep both cool.

I’ve got the big fans. I ended up getting a Hayden 678 cooler for mine.

 

[Doubeleive]

I had a thicker smaller (flexalite) installed before and it barely did anything above what the stock one did, that was also with 700w fans

 

[Geotrash]

You think that would be enough to keep the temps in check while towing? That factory external cooler is pretty small/thin.

That would be a lot simpler solution. Would be interesting if someone has done this and has some real before/after data

I do, but with a cold case or equivalent 2-row radiator. Sorry, I should have mentioned that.

For reference, I have pulled our 7000 camper over the spine of the blue ridge on 33 between standardsville and elkton, VA with our 2007 XL Denali, which had the factory engine and transmission cooling setup at the time, and the transmission peaked at 235°F, with the engine peaking around 230°F, IIRC. That route features a long, twisty and steep climb that generates as much heat in my rigs as anything I ever experienced living in Colorado, including the Eisenhower Tunnel, because it’s low elevation relatively speaking so the engine generates more heat because it’s putting out more power. And, the last mile or so requires 2nd gear, which heats the transmission up fast because there is no TC lockup in 2nd.

That experience freaked me out a little because it was before I knew what GM’s powertrain people say are the real limits of Dexron V and transmission temps, and triggered me to start adding bigger coolers to both of my rigs.

Conventional internet wisdom said that anything more than 200°F would kill a transmission quick, that you can’t overcool a transmission and that a Trucool 40K is the best solution. But after more research and my own field experience with 2 XL Denalis, all three are demonstrably false.

With the setup on my 2012, which includes the Cold Case radiator and Derale cooler, I run cooler than stock through that same pass, but on the engine only. The transmission temp pops up to 235°F, but does cool down faster once over the top, thanks to the cooling fan on the Derale. So I’m not convinced that the Derale setup is worth the trouble and cost over the factory cooler. In my opinion, the smart money is on a 2-row radiator and at least one 700w K5L fan - mine is on the driver’s side, with the stock 500w remaining on the other side.

 

[Krajniak]

Busy day!

yes gonna pull the rear passenger door apart today and figure out why my lock is not actuating.

 

[89Suburban]

yes gonna pull the rear passenger door apart today and figure out why my lock is not actuating.

I just went through this with mine.

 

[07Burb]

Probably needs a new door lock actuator. Pretty common for those to go out.

 

[Just Fishing]

Probably needs a new door lock actuator. Pretty common for those to go out.

I replaced my passenger side early on, and i have an intermittent issue on my driver side.

Passenger side got priority because it's harder to pay attention to.

Driver side, i just check that the lock actually locked.
Sometimes it won't unlock for me... lol

Passenger side, my hand came out looking like an angry cat had the sexy time with it.

Passenger side, i went with non oem via amazon.
Works fine, but it has different sound when closing the door.

I got a new old stock oem for the driver side.
It also came with the cable.

Amazon one did not.
Pita to get the stupid knock off clamp to clamp on the lock rod.

Get oem if possible.

 

[07Burb]

I replaced my passenger side early on, and i have an intermittent issue on my driver side.

Passenger side got priority because it's harder to pay attention to.

Driver side, i just check that the lock actually locked.
Sometimes it won't unlock for me... lol

Passenger side, my hand came out looking like an angry cat had the sexy time with it.

Passenger side, i went with non oem via amazon.
Works fine, but it has different sound when closing the door.

I got a new old stock oem for the driver side.
It also came with the cable.

Amazon one did not.
Pita to get the stupid knock off clamp to clamp on the lock rod.

Get oem if possible.

100% agree. Whenever possibly I always try and get OEM for parts like that. Paying the extra is usually well worth it for a lot of reasons.

 

[Fubar0715]

I had these on my Armada before throwing on Nokia Rotiiva AT2s for better winter performance.

The Michelins were really good all-seasons, great on the highway, adequate off-pavement, but for me in NH just couldn't offer the needed grip on snow/ice on hills.

I have the Cooper ATs in 275/55/20 on my Tahoe. Works fine in the snow and ice here in southern NH.

 

[Just Fishing]

I have the Cooper ATs in 275/55/20 on my Tahoe. Works fine in the snow and ice here in southern NH.

I have always been a fan of BFG AT's
I haven't tried the most recent version, but the version before they went with the fancy tread pattern on the sidewall is fantastic.
Long tread wear, and excellent traction.
Even in Snow, and decent on ICE.

I'm hoping they didn't change the tread depth like they did to the long trails.
Those long trails came stock on my S10 and lasted about 100k miles.

I had cooper studded snow tires on a spare set of wheels for my S10.
Those were absolutely fantastic for the first two years.
but after what I can only describe as flaps or fluffy ribs on the tread wore off, they were not nearly as good.
Still better in the snow and ice than the long trails, probably because of the studs.

I would use the coopers again for sure, just limit their use to actual snow weather.
Spare set of wheels and an easy/fast way to swap them on for max life.

the AT's are fantastic everywhere.
I didn't bother with studded tires after those.

The S10 went through 3 sets during it's long life (IIRC)
I also had them on my old K5.

Plan for the hoemare is to get a set once the current trash it's wearing wears out.