Last 2500 Suburban

CrazyDrei

Space Monkey
I'd put money this is the culprit. Washboard roads, etc, require more uptravel than something like rock crawling. Having lived in NE for several years, I can attest to the garbage road conditions up there (lived in Maine).

Find out what's limiting the up travel, add 2 to 3 inches, and I'd also bet the ride quality will drastically improve.

dvn4life1972,

I took this 2500 Sub on a washboard road for about 1 mile one time at 70psi, I still have PTSD from that 5 minute adventure. Deflated them to 35psi for the ride back and it wasn't that much better.

Same washboard in my 1500 Sub with 37" tires and 17" rims, at 18psi is butter smooth at above 15mph. Guess i am comparing apples to beef jerky and highly biased towards my 1500.

And yes, the roads in Maine, there are washboard roads in Death Valley that are smoother than newly paved roads in Maine, lol.
 
dvn4life1972,

I took this 2500 Sub on a washboard road for about 1 mile one time at 70psi, I still have PTSD from that 5 minute adventure. Deflated them to 35psi for the ride back and it wasn't that much better.

Same washboard in my 1500 Sub with 37" tires and 17" rims, at 18psi is butter smooth at above 15mph. Guess i am comparing apples to beef jerky and highly biased towards my 1500.

And yes, the roads in Maine, there are washboard roads in Death Valley that are smoother than newly paved roads in Maine, lol.

35 psi, even from 70 or 80 psi, isn't gonna help that ride on those types of roads. Load range E 10-ply tires or similar are just too stiff in the sidewalls for it. Take it down like you do on your 1500 and it should get closer to where you want it.

Your up travel, if only about an inch, is gonna be your single biggest contributor to that harsh ride both on and off road, but it's up to you what to do or not do.

Do you just like the look of the 37's on your vehicles? Just curious as to the personal reasoning for going to those.

Both decent rigs you have there, btw.
 

CrazyDrei

Space Monkey
35 psi, even from 70 or 80 psi, isn't gonna help that ride on those types of roads. Load range E 10-ply tires or similar are just too stiff in the sidewalls for it. Take it down like you do on your 1500 and it should get closer to where you want it.

Your up travel, if only about an inch, is gonna be your single biggest contributor to that harsh ride both on and off road, but it's up to you what to do or not do.

Do you just like the look of the 37's on your vehicles? Just curious as to the personal reasoning for going to those.

Both decent rigs you have there, btw.

dvn4life1972,

I wanted 40s but could not fit them because I would have to spend $350 on re-routing rear AC lines and heater lines. 37's fit and look perfect for what I need.

As far as dropping tire pressure to 18 in the 10 ply tires without a good sidewall, I am scared to get a puncture.

I am just keeping my 1500 for daily driving and off road adventuring and 2500 for towing and pavement only road trips. Both are great trucks I just don[t have te money right now to turn my 2500 into a perfect off road adventure truck, maybe one day when the 1500 dies I'll build up the 2500.

Thank you, I like both of the Subs as well.
 
dvn4life1972,

I wanted 40s but could not fit them because I would have to spend $350 on re-routing rear AC lines and heater lines. 37's fit and look perfect for what I need.

As far as dropping tire pressure to 18 in the 10 ply tires without a good sidewall, I am scared to get a puncture.

I am just keeping my 1500 for daily driving and off road adventuring and 2500 for towing and pavement only road trips. Both are great trucks I just don[t have te money right now to turn my 2500 into a perfect off road adventure truck, maybe one day when the 1500 dies I'll build up the 2500.

Thank you, I like both of the Subs as well.
It's really not a bad thing at all having an extra rig that's solid and will tow well enough, especially with some govt surplus pricing :)

FWIW 37's are the minimum accepted tire size to break even on a 14 bolt differential housing in terms of ground clearance. Otherwise smaller axles win with smaller tires, the pumpkin is just so ginormous. An alternative (if you're after clearance) would be to shave it, which I've never been a big fan of.

Looking forward to seeing how she develops!
 

CrazyDrei

Space Monkey
It's really not a bad thing at all having an extra rig that's solid and will tow well enough, especially with some govt surplus pricing :)

FWIW 37's are the minimum accepted tire size to break even on a 14 bolt differential housing in terms of ground clearance. Otherwise smaller axles win with smaller tires, the pumpkin is just so ginormous. An alternative (if you're after clearance) would be to shave it, which I've never been a big fan of.

Looking forward to seeing how she develops!

dvn4life1972,

I think you nailed this one. I have a GM 8.6" 10 bolt on my 1500 with 12.5" ground clearance, vs 14 bolt FF on the 2500 with 8.5" ground clearance sitting on 33" tires. That extra 4" makes a HUGE difference. So even if I do go to 37s on my 2500 I'm still at 10.5" ground clearance. If I go to 40s that I don't think I could fit without a solid axle up front I'm still looking at 11" of ground clearance under the pumpkin.

I'm not shaving the diff. Need that surface area for heat dispersion. Bigger tires will need at least a bump upto 4.10 gears and they run hotter than 3.73s, where i could always touch the diff cover with my bare hand even after long highway cruises.

I am also looking forward to what happens with the 2500, I am sure in time I will run 40s on it with just some body spacers.
 

FishinGuns

New member
FishinGuns,

What kind of TPMS sensors are you using? I've been running the cheapest 315 MHz eBay sensors and never ever had any trouble with them no matter if I am running 30psi or 80psi in all the tires. GM did do one thing right, it's ridiculously easy to re-program them without any dealer tools in less than 5 minutes. Makes changing from one to second set of tires a breeze.
I assume they are factory TPMS sensors, since there is only 45,000 on the clock. I don’t know for sure though. Plan to mess with them tomorrow hopefully. Bumped down to 45psi and the dash is yelling at me. Hoping a simple computer change is all that’s needed!
 
I assume they are factory TPMS sensors, since there is only 45,000 on the clock. I don’t know for sure though. Plan to mess with them tomorrow hopefully. Bumped down to 45psi and the dash is yelling at me. Hoping a simple computer change is all that’s needed!

Unfortunately it's the computer (BCM I believe) that causes the TPMS light on the dash, not the sensors themselves. I was able to get a GM dealership to bump the psi parameter down to 50 psi before they set off the dash light, from the factory 65psi lower limit (3500 Chevy Express). I'm sure alot of dealerships might not be willing to do that though, for liability.
 

CrazyDrei

Space Monkey
Unfortunately it's the computer (BCM I believe) that causes the TPMS light on the dash, not the sensors themselves. I was able to get a GM dealership to bump the psi parameter down to 50 psi before they set off the dash light, from the factory 65psi lower limit (3500 Chevy Express). I'm sure alot of dealerships might not be willing to do that though, for liability.

MichaelK10,

Interesting, I did not even think of that lower psi limit, just assumed that it was set for all tires to be within 5psi. I wonder if any independent shop with a tech2 can adjust it for you if the dealer will not.
 
MichaelK10,

Interesting, I did not even think of that lower psi limit, just assumed that it was set for all tires to be within 5psi. I wonder if any independent shop with a tech2 can adjust it for you if the dealer will not.
Hopefully that's the case. I don't know enough about the tech 2 yet. I tuned my '14 Sierra engine/trans with Black Bear Performance and they weren't able to change any of the BCM parameters (like stabilitrac) so I'm not sure what kind of magic the dealership uses.
 

CrazyDrei

Space Monkey
Hopefully that's the case. I don't know enough about the tech 2 yet. I tuned my '14 Sierra engine/trans with Black Bear Performance and they weren't able to change any of the BCM parameters (like stabilitrac) so I'm not sure what kind of magic the dealership uses.

MichaelK10,

Black Bear is a great solid tune. I am lucky enough to have an 2000 Sub back when they still had PCM instead of the ECM, TCM, BCM that my GMT900 has. I'm sure a Tech2 can do it, but not sure.

Good luck and when you figure it out do let us know.
 

FishinGuns

New member
Had an independent shop take my computer low pressure warning down to 35psi. Life is good! I’m running 40psi cold at all four corners, just tooling around, no load. I’m not going to say night and day, but it is significantly better!
 
Had an independent shop take my computer low pressure warning down to 35psi. Life is good! I’m running 40psi cold at all four corners, just tooling around, no load. I’m not going to say night and day, but it is significantly better!
Awesome, the right tire pressure makes a huge difference. Do you know what type of scantool they used?
 

CrazyDrei

Space Monkey
Putting my 2500 Suburban towing capacity to good use.

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My trusty 1500 Sub needed a 200 mile ride home after the last adventure. Compared to the 10,000# trailer I usually tow I didn't even feel like I was towing another Suburban. Canoe on the roof, well that was nerve wrecking considering that it was attached to factory cross bars.
 

CrazyDrei

Space Monkey
First official trip into the wilderness!

Two years ago when I bought this mythical 2500 Suburban I decided to test it's off-road superiority and went on an easy drive, mostly highway but there was about 1/2 mile of dirt to a really big can of PBR in the the Nevada Desert. The truck did OK on the highway, ride was rough but bearable. And then came the dirt, it was outright miserable and from that day on I have firmly stood against taking a 2500 chassis off road or even on "overland" dirt roads.

This is all about to change...

Two weeks ago I took my trusty 2000 K1500 Suburban deep into the North Maine Woods, it was a great trip however 80 some miles from camp and 260 miles from home the transmission went out. I got home safely with the kids however had to leave my pop-up camper in the wilderness for a few days. Last week the kids and I got into the white Sub and went back to the North Maine woods to recover the camper and spend a couple more days exploring.

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I chose to leave the house later than usual so that the kids could nap for the first two hours of the drive and give me some peace of mind. This would get us to the camper at around 7-7.30pm and at the campsite around 8.30pm.

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2 miles, YES TWO MILES! after getting onto the legendary Golden Road, I see steam billowing out from under the hood. I was not even going fast, maybe 25-30mph. Yep lost a heating hose connector.

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To make things worse it was too late and i would not make it to a car parts store in time to fix it. Had to do an emergency roadside fix. Luckily I have the parts I needed to fix and keep going. Including topping off 3 gallons of coolant that I lost.

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I connected the feed and return heater core hoses with a /2" metal pipe that I had in my tool kit (just for this particularly common GM failure).

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For some reason I did not have any hose clamps so gaffers tape had to do. I topped off the 3 gallons of coolant and we continued on our way to pick up the camper at 7.45pm. And headed to to a closer campsite than we originally planned on going to. Other than having no heat, we made it to our campsite around 9pm.

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Driving dirt roads in the 2500 Suburban was a slow and unpleasant process compared to driving the same roads in the 1500 Suburban. Difference was about 1/2 the speed, in other words 23 miles usually takes me 30 minutes to drive in the 1500 and it took over one hour in the 2500.

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Around 10pm it started raining, sometime during the night rain changed to snow. Weatherman said it was supposed to be 58F and partly cloudy, he was wrong.

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It was snowing but not sticking all morning.

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Kids had some fun throwing rocks and sticks into the nearby stream.

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They had more fun warming up by the fire.

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Snow started sticking to the trees, and after a couple hours eating and playing games int eh camper I decided to call it a day, pack up and head home.

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Last week in April in the North Maine Woods, and its snowing.

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Suburban had absolutely no problems pulling the 1,200# pop up, however the rutted out dirt roads were rough on the truck and made going slow.

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Temperature dropped to 32F and snow started sticking to the ground. It was cold in the truck with no heat. We spent nearly three hours driving 40 miles to get off the dirt roads.

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Finally made it to car parts store for 3 feet of heater hose, 3 hose clamps and a heater core plastic connector. Quick and easy fix and the heat is working again fro the drive home. Kids are now warm and cozy without all the winter jackets and pants!

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This is the connector that broke after 2 miles of bouncing round on dirt roads. I did have a spare one in my toolkit but without extra heater hose it would have broken off too so I decided to bypass the heater cores when i did a quick roadside fix.

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Found a tank on the way home.

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Trying to not exceed the load capacity of the roof rack with a helicopter.

We made it home with no other problems, well I do have to replace another upper control arm because less than 100 miles on dirt wore my ball joint out, which I was expecting. With everyone that has 1500 trucks and is dreaming of a 2500 chassis for overlanding, don't. Unless you plan on spending more on suspension/lift upgrades than you spent on the truck the extra weight of unnecessary "heavy duty" parts is just not worth it.

I like to drive quick off road, I like keeping my weight down and ground clearance high yet center of gravity low. All this simply points to the 1500 chassis as far superior to the 2500 off road. And this short little adventure proved my point to me.

If I were to build this 2500 Suburban for actual overland travel, I would put a front coiolver lift kit, 6" diff drop kit and 40" tires. As well as 4.56 gears and a Detroit rear locker. At this point I will be looking at $10,000 in upgrades alone to make this 2500 chassis be remotely comparable to my low budget 1500 setup.
 

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