Chevrolet Suburban 3500 Questions

[Bigburb3500]

Woohoo! I hope you love it! I’m curious what you asked for in your request.

I received my tune files earlier this week from Justin (quick turnaround), so I’ll get them uploaded to the rig over the weekend. He mentioned that on these trucks, mid-grade 89 can be worth the small additional cost in improved fuel mileage. So I’ll run it and see how it goes.

I am so excited for it based on what you and others have hyped up Blackbear to be!

I put on the form that it is up to their discretion. I use my truck as a daily driver and family hauler, but need/want it for long term reliability and heavy duty use. What did you list down for preferences?

Really? These trucks do noticeably better on mid-grade+? I just did 1000+ miles this week in the truck I could have reported back, but will refill this month and see what comes of it. I think Costco has 87 and 91… will see what the cost difference is too.

 

[Bigburb3500]

Also, did the transfer case and front diff fluid. Transfer case had more on the magnet than expected but seems “normal” based on videos I watched. Front diff fluid was garbage. It was very smelly and funky color. So much for “dealer maintained.”

Glad I got the new fluids in and SUPER easy to do. Easier than an oil change.

 

[Geotrash]

Also, did the transfer case and front diff fluid. Transfer case had more on the magnet than expected but seems “normal” based on videos I watched. Front diff fluid was garbage. It was very smelly and funky color. So much for “dealer maintained.”

Glad I got the new fluids in and SUPER easy to do. Easier than an oil change.

Nice! I guess that’s the advantage of the commercial purpose pedigree - all fluids can be easily changed.

 

[Geotrash]

Also, did the transfer case and front diff fluid. Transfer case had more on the magnet than expected but seems “normal” based on videos I watched. Front diff fluid was garbage. It was very smelly and funky color. So much for “dealer maintained.”

Glad I got the new fluids in and SUPER easy to do. Easier than an oil change.

I had only suggested that I don’t want to lose 87 octane capability, that I tow often, and that I hoped they could optimize for transmission longevity as well.

 

[Bigburb3500]

I had only suggested that I don’t want to lose 87 octane capability, that I tow often, and that I hoped they could optimize for transmission longevity as well.

Ok, that’s hopefully what I conveyed. I did ask to see if they can change the Tow/Haul mode to be more aggressive/better optimized for towing and hauling while the normal be as “normal” as possible.

 

[Geotrash]

Ok, that’s hopefully what I conveyed. I did ask to see if they can change the Tow/Haul mode to be more aggressive/better optimized for towing and hauling while the normal be as “normal” as possible.

If it helps, I find the tow/haul mode settings to be perfect for our 7500 lb camper from the factory. But I once asked if they could dial them down a bit on my ‘07 because they were too aggressive, but for some reason they couldn’t — don’t remember why.

 

[Bigburb3500]

Alright, so to all of you watching this thread, I’m CONTEMPLATING doing a small lift and a few other things. One item that I think I should do with the lift is add new upper control arms. The issue here is these appear to be that the Suburban 3500 has specific control arms… I find that nearly impossible to believe given how GM loves parts sharing. Can someone help me cross reference this and see if there is an aftermarket control arm that would work?

https://g.oempartsonline.com/oem-parts/gm-front-upper-control-arm-23324185

 

[calsdad]

Alright, so to all of you watching this thread, I’m CONTEMPLATING doing a small lift and a few other things. One item that I think I should do with the lift is add new upper control arms. The issue here is these appear to be that the Suburban 3500 has specific control arms… I find that nearly impossible to believe given how GM loves parts sharing. Can someone help me cross reference this and see if there is an aftermarket control arm that would work?

https://g.oempartsonline.com/oem-parts/gm-front-upper-control-arm-23324185

Duraburb has a video where they said that the frame on the Suburban 3500 you have - is the same frame as the previous 2 generations of 2500 Suburban - so the upper A-arms should be the same geometry as those. The fact that there's no other vehicles listed for the part number you posted - might not mean anything. Even a minor change - like durometer on the bushings or something like that - would end up with a different part number.

I put Cognito upper A-arms on my 2010 GMC Yukon 2500 - if I remember correctly it was the same part number for my Yukon as for the Suburban 2500, and Sierra and Silverado 2500 and 3500.

 

[Bigburb3500]

Duraburb has a video where they said that the frame on the Suburban 3500 you have - is the same frame as the previous 2 generations of 2500 Suburban - so the upper A-arms should be the same geometry as those. The fact that there's no other vehicles listed for the part number you posted - might not mean anything. Even a minor change - like durometer on the bushings or something like that - would end up with a different part number.

I put Cognito upper A-arms on my 2010 GMC Yukon 2500 - if I remember correctly it was the same part number for my Yukon as for the Suburban 2500, and Sierra and Silverado 2500 and 3500.

Thank you for this! I will look into this further

 

[calsdad]

Thank you for this! I will look into this further

Another thought came to mind - and again I got this from the Duraburb video ( you might want to go search that out): If I remember correctly Duraburb said that the Suburban 3500 had the "new" style 8 lug circle of 180mm or whatever it is. The "old" lug circle was like 8x 6.5" or something like that. That *might* mean that the upper A-arms are indeed different than anything else because they're adapting from the holdover 2500 frame - to the spindles that work with hubs for the 8x180mm bolt circle or something like that. I don't know - I'm just guessing. But - again - that might not mean that the upper A-arms are actually any different than say A-arms from the earlier 2500 Suburban/Yukon/Sierra/Silverado - it could just be that the ball joint is different than the "old" ball joint - so the A-arm is the same - but the ball joint is different. Again - don't know - I'm just guessing.

What you probably need to do is take some measurements or match up your upper A-arms - with an A-arm from an older truck - and see if they're the same. I might have my old one's still hanging around somewhere - I'd have to go look. You might also be able to get some measurements from a place like Cognito - to see if they'd match up. Sometimes places like that are willing to work with you - just because it gives them info they can apply towards their product line.