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Review: Thermal R&D 3" Catback

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11
Reactions
18
Points
2
Location
Atlanta, GA
Vehicle
2025 Explorer ST
#1
A couple of weeks ago, I upgraded to the Thermal R&D 3" Catback system to give my ST the sound it deserves. The stock exhaust felt underwhelming, likely because of government noise regulations, and as someone who’s owned high-performance cars, I really missed that powerful, aggressive tone.

After the installation, the difference was unmistakable. The car feels alive, with a fantastic cold start and a deep rumble on command—plus, no cabin drone, which is a huge plus. I’d rate it 5 out of 5 for sound and look.

That said, I might be getting a little more practical. My ST is my daily driver and family car, and there are times—like driving through the neighborhood at night or taking the family on trips—when the sound is a bit much. I’m wondering if a 2.5" version might have been quieter under normal conditions and only gone aggressive under wide-open throttle. I really appreciate the adjustable exhaust in my Corvette C7, where I can select the exhaust note with different driving modes, and even the stock sound of my RAM TRX is aggressive without being overwhelming inside the cabin.

Knowing what I know now, would I buy it again? Maybe. If a 2.5" offered a quieter sound in everyday driving with more roar on demand, I’d probably go that route. But for pure sound quality and presence, the 3" is still a great choice—just maybe more so if you’re less concerned about keeping things family-friendly.
 

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1,373
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656
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Location
Nevada
Vehicle
'20 Raptor, '22 Explorer ST, '14 GT500, '03 F150
#2
You’re full of good writeups! I’m sure it will be very helpful to some people.
 

Messages
102
Reactions
34
Points
27
Location
Chicago IL
Vehicle
2022 Explorer ST
#3
I had the 2.5'' on my 2020 and I recently got the 3'' for my 2022. I went with the 3'' because I wanted a bit more volume, and I got it.

2.5'' IMO is perfect for the person that wants an aftermarket exhaust and is only loud when going WOT and moderately loud on cold starts (once warmed up, only a faint rumble). the 2.5'' still sounds great when revving it and when going WOT. With the 2.5'' I took many overnight trips across states while the family slept.

With the 3'', so far no complaints from the kid or the wife. But, they expected it, as I warned them this one might be a little loud.
 

Messages
35
Reactions
14
Points
2
Location
NJ
Vehicle
2023 Explorer ST
#4
Thermal is one of those absolute “must-haves” after buying an Explorer ST. I originally resisted, learned my lesson, and rectified the situation within a month.
 

OP
F
Messages
11
Reactions
18
Points
2
Location
Atlanta, GA
Vehicle
2025 Explorer ST
Thread Starter #5
@Eljaber, thank you for sharing your input about the 2.5" Catback. Now I'm thinking of selling my 3" and buying the 2.5" based on your experience.
 

Messages
1,373
Reactions
656
Points
162
Location
Nevada
Vehicle
'20 Raptor, '22 Explorer ST, '14 GT500, '03 F150
#6
@Eljaber, thank you for sharing your input about the 2.5" Catback. Now I'm thinking of selling my 3" and buying the 2.5" based on your experience.
I’m sure someone might want to do the opposite of what your doing, so you might be able to trade your 3” with someone that has a 2.5”.
 

UNBROKEN

4000 Post Club
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Location
Houston, TX, USA
#7
I’d just add a couple of Vibrant Ultra Quiet resonators at the end of the downpipes. It’ll tame it down for a lot less money and hassle than swapping exhausts.
 

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194
Reactions
79
Points
27
Location
Jessup, MD, USA
#8
I had the 2.5'' on my 2020 and I recently got the 3'' for my 2022. I went with the 3'' because I wanted a bit more volume, and I got it.

2.5'' IMO is perfect for the person that wants an aftermarket exhaust and is only loud when going WOT and moderately loud on cold starts (once warmed up, only a faint rumble). the 2.5'' still sounds great when revving it and when going WOT. With the 2.5'' I took many overnight trips across states while the family slept.

With the 3'', so far no complaints from the kid or the wife. But, they expected it, as I warned them this one might be a little loud.
Did you have downpipes on either of those?
 

Messages
102
Reactions
34
Points
27
Location
Chicago IL
Vehicle
2022 Explorer ST
#10
@Eljaber, thank you for sharing your input about the 2.5" Catback. Now I'm thinking of selling my 3" and buying the 2.5" based on your experience.
No better time than now! Lethal started their black Friday sale and the 2.5'' is $1,200.
 

Messages
35
Reactions
14
Points
2
Location
NJ
Vehicle
2023 Explorer ST
#11
Ive had a sensational experience getting parts from Alec at ForzaMotorworks. Check him out for Thermal pricing as well
 

Messages
40
Reactions
13
Points
2
Location
Charlotte
Vehicle
2024 Explorer ST
#12
like driving through the neighborhood at night or taking the family on trips—when the sound is a bit much.
I have downpipes and the 3" thermal. I can easily go light on the gas for neighborhood driving without her sounding too obnoxious. Sure if you goose it to get on a main road or something, yea no stopping that sweet symphony! As for the family , my wife and daughter like it. Highway driving is hardly noticeable unless its time to pass that asshole going 55 in the left lane.

While everyone's tastes are different, you explain the reality. The 3", I can say especially with downpipes, are not for the faint of heart when it comes to sounds. If anyone is looking more for a stock+ sound, the 2.5" is most definitely worth the look. The 3" sings at anything other than the lightest touches of the accelerator.
 



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