Upgrade package - exhaust/suspension/wheels

[Danneman]

I hope I put this in the right category, apologies if I did not.

I'm looking to make a few changes to my 2018 Tahoe LT, but the kind of upgrades I prefer to stick to with for my daily driver are things that the factory could just as easily have made - like selected parts from the next trim level up.

What I'm hoping is that someone could confirm that these changes - together, as a package - will work for my vehicle and should deliver an overall improved driver experience, as in a GenMo engineer would say "yeah, this is fine, you're not doing anything inappropriate for the vehicle, go for it."

1. "Performance Exhaust" - part #19329322 - this is appears to be the cat-back system that came on the 2018 RST, but for the 5.3L.
2. Magnetic Ride Control - I've seen a lot on people wanting to revert back to conventional suspension after their MRC needed maintenance due to cost, but I can't find a lot on going TO it. Is this done? Is there a kit?
3. 20" wheels - I know the speedometer would need to be dealt with, I think I heard I might need to have something in order for a mechanic to adjust it, but that not all Tahoes have it. Is that right? Are there other implications, like shift points? ECU retune?

Thanks for any help. -DW

 

[Brian71]

I can only answer the wheel question

In my case my Tahoe came with 22 inch wheels. In the winter I have a separate set of wheels/tires. They’re off my old 06 Tahoe. They’re 17 inch rims. The tire size of the 17 inch wheels vs. The 22 inch wheels are virtually the same. I’ve swapped the 22 inch wheel/tire combo for 17 inch wheel/tire combo for 2 seasons. I’ve had zero issues. No issue with speedometer or shift points.
I’m planning on replacing the 22 inch wheels for 20 inch wheels

 

[Doubeleive]

1. Waste of money, muffler shop can build you something cheaper on the spot, but otherwise it should bolt right up
2. no you cannot upgrade to MRC, you maybe could if you had a ton of money and complete wiring harness and programming and lots of free time to experiment
if you are looking to tow and not have sag you could easily add helper bags, otherwise you could change over to bilsteins 4600/5100 or fox adjustables, etc
3. wouldn't worry about the speedo at worst it would be 2-5mph off, it can be corrected with a speedo programmer, nothing else required

 

[CMoore711]

@Doubeleive is spot on. Don't waste your money on a cat-back exhaust system.

1. Just purchase a weld-in muffler that you're local exhaust shop can weld in and it'll cost you $200-$300 (max) for the muffler and labor. I would consider removing the exhaust flapper valve located after the muffler and replace with a straight piece of pipe. This exhaust flapper functions for the AFM.

2. Changing to MRC suspension would be a huge undertaking and cost a lot of money; Not so much for the shocks and struts themselves but as mentioned above more so on the electronic side of things. Modifying factory body harnesses and connections to all 4 corners of the vehicle, new/modified BCM (Body Control Module), etc. etc. It'd be more cost affective to trade in your vehicle for a different one with MRC from the factory if you wanted MRC that badly.

3. You don't have to extensively modify the ECM to adjust for different tire sizes. This device here would work well for your application:

Range Technology 22454 Pulsar LT for 2014-2018 1500 5.3L, 2015-2020 SUV

The 22454 Pulsar LT is a new in-line module for 2014-2018 Chevrolet Silverado 1500 and GMC Sierra 1500 5.3L, and 2015-2020 5.3L/6.2L SUVs, that offers complete adjustability of many features, all from your steering wheel controls. Without modifying your truck's ECM, Pulsar LT offers you the...

www.rangetechnology.com

In addition to making tire size adjustments to your speedo, it also provides a few other user friendly adjustments that will improve overall driver experience. And with the money you'll save from not buying a complete cat-back exhaust system it should fit into what you're looking to spend.

How many miles are on your '18 Tahoe?
Have you ever replaced any of the suspension components (shocks, struts, control arms, sway bar bushings and links, tie rods) or still on all original parts?

 

[15burban]

For the "wheels" going to be a bigger rim won't effect your speedometer as long as the tires on the new rims are the same size. If you go bigger or smaller with the tires then you're speedo will be off.

 

[Danneman]

For the "wheels" going to be a bigger rim won't effect your speedometer as long as the tires on the new rims are the same size. If you go bigger or smaller with the tires then you're speedo will be off.

 

[Danneman]

Thanks everyone for their thoughts. If there is a non-zero chance that my vehicle already has some or all of the MRC wiring, does anyone know how I could confirm? What would I look for, where?

 

[tooleyondeck]

Thanks everyone for their thoughts. If there is a non-zero chance that my vehicle already has some or all of the MRC wiring, does anyone know how I could confirm? What would I look for, where?

You could seriously do a complete airbag suspension for less than what it would cost to rip out your entire wiring harness, find out what you do and don't have, hunt down each component from GM (probably have to do that based on a VIN for a vehicle that has MRC), install all the necessary components to support the MRC system, and have your ECU reprogrammed. Just typing all of that was stressful lol

 

[Coolman1987us]

This device here would work well for your application:

The mpvi3 from HP tuners is $400. The license for my 08 hoe was $100 (different for each generation). I not only shut off AFM but can modify hundreds of other settings for less than this waste of money.

 

[Doubeleive]

You could seriously do a complete airbag suspension for less than what it would cost to rip out your entire wiring harness, find out what you do and don't have, hunt down each component from GM (probably have to do that based on a VIN for a vehicle that has MRC), install all the necessary components to support the MRC system, and have your ECU reprogrammed. Just typing all of that was stressful lol

Um where are these "components" going to plug in?

 

[CMoore711]

The mpvi3 from HP tuners is $400. The license for my 08 hoe was $100 (different for each generation). I not only shut off AFM but can modify hundreds of other settings for less than this waste of money.

Yes absolutely; HP Tuners has infinite more capability, adjustments, and customization over the Pulsar LT device and is a great tool to tune vehicles with.

However, there is a learning curve to HP Tuners and if you don't spend some time educating yourself and understanding the impacts of the adjustments/changes you're making with HP Tuners it is possible to cause harm or damage to the drivetrain.

Given the context of the OP's post the initial concern was would it be required or possible to adjust the speedometer due to a change in wheel and tire size. OP seems to be interested in GM Factory type parts and upgrades referencing GM Part numbers and other factory options. There is also no mention of AFM or disabling it by the OP. I in no way gathered that he's interested in going down the "learn how to tune my own vehicle with HP Tuners software" rabbit hole; But yes you can use HP Tuners to adjust the speedometer for different size tires.

 

[Danneman]

Yes absolutely; HP Tuners has infinite more capability, adjustments, and customization over the Pulsar LT device and is a great tool to tune vehicles with.

However, there is a learning curve to HP Tuners and if you don't spend some time educating yourself and understanding the impacts of the adjustments/changes you're making with HP Tuners it is possible to cause harm or damage to the drivetrain.

Given the context of the OP's post the initial concern was would it be required or possible to adjust the speedometer due to a change in wheel and tire size. OP seems to be interested in GM Factory type parts and upgrades referencing GM Part numbers and other factory options. There is also no mention of AFM or disabling it by the OP. I in no way gathered that he's interested in going down the "learn how to tune my own vehicle with HP Tuners software" rabbit hole; But yes you can use HP Tuners to adjust the speedometer for different size tires.

You got it, bud - thank you. For a toy car or my shifter kart, I don’t mind learning how to do things and inevitably messing up in the process - but my daily driver has a family job to do and it’s a zero fail mission, no time for me to work my way up the curve.

The shop foreman at my dealer said that he believes there’s something in this year Tahoe that allows for easy adjustments, but not all models had it - so was wondering if that resonated with anyone. If it’s isn’t an adjustment he can/will make as a GM dealer mechanic, then I don’t want it for this vehicle.

By the way Matt Head was amazing to work with on my fog lamp harness, got his name from this forum. I have an email out to him to see if he knows anything about the MRC harness.

 

[91RS]

The GM exhaust is made by Borla, so the quality is good. I prefer the sound of Corsa but if you like the Borla sound, go for it. Sure, you can go to an exhaust shop and have something welded in but you’re very limited for options, won’t be able to hear it first, and it’s usually a low quality muffler. With a cat back, you’re paying for an all stainless steel construction and the tip(s) are generally much higher quality. You can also install a cat back yourself.

Get Fox coilovers (they come setup for an 2” lift but can be set to stock ride height) and the matching rear shock, that will ride better than MagRide could ever hope to.

The stock 275/55/20 and 285/45/22 are so close in overall diameter that I wouldn’t worry about the speedometer, it’ll be 1-2 MPH off at the most.

 

[Danneman]

The GM exhaust is made by Borla, so the quality is good. I prefer the sound of Corsa but if you like the Borla sound, go for it. Sure, you can go to an exhaust shop and have something welded in but you’re very limited for options, won’t be able to hear it first, and it’s usually a low quality muffler. With a cat back, you’re paying for an all stainless steel construction and the tip(s) are generally much higher quality. You can also install a cat back yourself.

Get Fox coilovers (they come setup for an 2” lift but can be set to stock ride height) and the matching rear shock, that will ride better than MagRide could ever hope to.

The stock 275/55/20 and 285/45/22 are so close in overall diameter that I wouldn’t worry about the speedometer, it’ll be 1-2 MPH off at the most.

Thank you much. Do you have a part or model number for the coil overs you mentioned?

 

[91RS]

Check out shocksurplus.com. They also have their own reviews on a bunch of the stuff. Also check out magdelete.com, they have some great complete kits. You might be able to contact them and buy without the defeat device and save money since you wouldn’t need it. I suggest them also because they have a bolt in kit for the Bilstein 5100, which is another great option.

 

[Danneman]

Check out shocksurplus.com. They also have their own reviews on a bunch of the stuff. Also check out magdelete.com, they have some great complete kits. You might be able to contact them and buy without the defeat device and save money since you wouldn’t need it. I suggest them also because they have a bolt in kit for the Bilstein 5100, which is another great option.

Thanks!

 

[RobH]

. . .

The stock 275/55/20 and 285/45/22 are so close in overall diameter that I wouldn’t worry about the speedometer, it’ll be 1-2 MPH off at the most.

What 91RS ^^^ said. When most people think about wheel size and/or tire size they are thinking about something like 275/55/20 or 285/45/22.

What is pertinent for the speedometer is the over all circumference of the wheel/tire combination rolling down the street. The circumference (distance around the tire tread) is Pi X diameter.

So the overall diameter of the wheel/tire combination is what affects the speedometer. You can use the calculator in the upper left corner of the website link below to determine tire size characteristics.

Tire Size Calculator

The best tire size calculator. Use our tire size calculator to find tire size specs and suggested tire sizes. Then check prices for all available tire sizes.

tiresize.com

 

[tooleyondeck]

Um where are these "components" going to plug in?

exactly, probably need an entire harness, ECU/BCM, and fuse box from an MRC-equipped vehicle to make it work.

 

[BacDoc]

A whole summer has gone by and I’m curious to hear what you did.

Upgrades are always fun and wheels and tires give a lot of bang for the buck. One of my favorite things is driving off on new tires!

I understand the OPs concerns about OEM and “daily driver” status so id like to know how his upgrades turned out.

I had similar concerns but for exhaust upgrades I will go aftermarket not just for the price but for quality of results. There are some good YouTube channels on exhaust options for 5.3l and 6.2l. Sometimes just a muffler change and resonator change/delete can make a difference for a fraction of the cost of OEM cat back exhaust and have no effect on factory warranty.

 

[Danneman]

Thanks for the reminder to follow up, yeah family comfort / daily driver still the priority for this vehicle. For exhaust I went with the “Chevy performance” cat-back made by Borla for the 5.3, includes the anti-drone valve and I’m quite pleased with the sound. (It was never about performance with this vehicle, I have a race vehicle if I want to have more fun and experiment and take risks etc.). Taking it easy with the family it just sounds like a strong v8 while getting up to speed, clearly audible but not obnoxious, and settles down nicely to a volume tolerable for my frequent 5 hr trips. Carbon fiber borla tips were an indulgence but look sweet. Got the borla intake as well, knowing that it makes zero difference (sound or performance) unless you’re standing on the throttle, and even then maybe not performance because I haven’t timed or measured anything and I don’t care to. Just saying, open the taps now and it’s a great soundtrack, and that’s all I wanted, for my v8 to sound like a v8 again. Tires have another year or so on them so waiting for them to wear out before doing shocks/struts and 20” OEM 5 spoke wheels. Thinking upgraded sway bar as well at that time, for slightly more controlled feel through turns, but have more research to do on that one.

The way my dad used his 99 Yukon, which I had bought from him and relied HEAVILY on this forum to help keep it running great, was like a family luxury truck. I love that concept of being those three things at the same time, and doing them all pretty well. With these changes I think I’m keeping with that intent, and it’s going well so far. At some point I’ll summarize everything I’ve done and post it for all.