❄️ Review: Modalworks C63 M177 radiator upgrade solved my heatsoak issue
Newbie
Joined: Dec 2020
Posts: 6
Likes: 2
2017 c63s coupe
SPONSOR
Joined: Dec 2019
Posts: 334
Likes: 97
From: Texas
W205 C63
Manufacturing costs have gone up dramatically on these units.
We strive for fair pricing on all of our products and these are unfortunately expensive to make. We stand behind them as the best performing intercooler radiator option.
We have a few garage sale coolers on our site at a discount so you can pick those up to save some $$.
We strive for fair pricing on all of our products and these are unfortunately expensive to make. We stand behind them as the best performing intercooler radiator option.
We have a few garage sale coolers on our site at a discount so you can pick those up to save some $$.
Member
Joined: Mar 2023
Posts: 161
Likes: 32
18 c63 s sedan
Nice review! I was debating on going with Modalworks after a recent puncture to my passenger side OEM radiator from a rock on the highway but ended up with CSF's 3 piece kit. I'm now interested in adding MW's new divorced transmission cooler!
I did CSF via FCPEuro for 3 main reasons:
1. They have removable rock guards for all 3 coolers (I have a ton of construction around me, so a puncture could happen at any second)
2. FCP euro has liftetime warranty, so if I have another puncture scenario, I can get a free replacement.
3. CSF has been around for a long time and while they don't have great data backing the w205 C63 specific application, they've had great reviews & results on many other platforms for years.
Looking at the stock radiators compared to CSF (and I'm sure Modalworks too), they are TINY and extremely thin. I would think any upgrade (maybe other than Chinese garbage) would be beneficial.
@Jimmy_c63s - what are the ambient air temps during the time you captured your oil & trans temps? Was it warm outside?
@Bosnianc63 - how are you enjoying the Modalworks intakes on the PTG1000s? I am running a very similar set-up to you but on stock intakes. Do they MW intakes providing any additional cooling benefits?
I did CSF via FCPEuro for 3 main reasons:
1. They have removable rock guards for all 3 coolers (I have a ton of construction around me, so a puncture could happen at any second)
2. FCP euro has liftetime warranty, so if I have another puncture scenario, I can get a free replacement.
3. CSF has been around for a long time and while they don't have great data backing the w205 C63 specific application, they've had great reviews & results on many other platforms for years.
Looking at the stock radiators compared to CSF (and I'm sure Modalworks too), they are TINY and extremely thin. I would think any upgrade (maybe other than Chinese garbage) would be beneficial.
@Jimmy_c63s - what are the ambient air temps during the time you captured your oil & trans temps? Was it warm outside?
@Bosnianc63 - how are you enjoying the Modalworks intakes on the PTG1000s? I am running a very similar set-up to you but on stock intakes. Do they MW intakes providing any additional cooling benefits?
Long time I know. But do you have the CSF part numbers for all 3 coolers? I found the center main b it not the twins
Super Member
Joined: Apr 2006
Posts: 702
Likes: 30
From: Leesburg, VA
2017 C63S
any upgrades since this is 3yrs old?
Thanks for the detailed write-up. We love to see customers back up our testing!
The released design was actually version 5. We tested different core thicknesses, fin density’s, tube channel geometry and flow paths to ultimately settled on this configuration. Those saying all of the cooling options are the same are flat out wrong.
We purchased the china kits to evaluate and quickly moved away from them. Bigger is not always better… fluid flow is tricky and not as straight forward as some may think.
The released design was actually version 5. We tested different core thicknesses, fin density’s, tube channel geometry and flow paths to ultimately settled on this configuration. Those saying all of the cooling options are the same are flat out wrong.
We purchased the china kits to evaluate and quickly moved away from them. Bigger is not always better… fluid flow is tricky and not as straight forward as some may think.
Senior Member
Joined: Dec 2025
Posts: 423
Likes: 37
From: Keep it simple - keep it OEM
AMG C63s Coupe
I think the OEM Radioator A0995005903 has no cooling problem (in OEM setup) but in my mind a quallity problem ( plastik cracks ) No updated since.
Some of the radiators in your list looks for me same or similar only color or price is different.
Your Radiator from PWR look realy different. I dont know PWR - can you tell me more or give me a www url link ?
Thanks
Last edited by C63s_Jack; Dec 23, 2025 at 02:05 PM.
Super Member
Joined: Oct 2015
Posts: 908
Likes: 133
From: Tampa, FL
'17 AMG S63 Convertible, '17 AMG C63S Edition 1 Coupe
Your Radiator from PWR look realy different. I dont know PWR - can you tell me more or give me a www url link ?
I also was interested in the Modalworks setup, but their Stage 2 kit (with all 3 upgraded coolers) has been sold out/not available for MONTHS...
https://modalwork.com/collections/w205-c63
Thread Starter
MBWorld Fanatic!
Joined: Sep 2016
Posts: 1,720
Likes: 608
From: Australia
⏱️ 700HP Facelift converted C63 S Coupe with Drexler 3.06 plated LSD
50,000km with the ModalWorks PWR coolers - insanely robust
Thanks for your thread about this.
I think the OEM Radioator A0995005903 has no cooling problem (in OEM setup) but in my mind a quallity problem ( plastik cracks ) No updated since.
Some of the radiators in your list looks for me same or similar only color or price is different.
Your Radiator from PWR look realy different. I dont know PWR - can you tell me more or give me a www url link ?
Thanks
I think the OEM Radioator A0995005903 has no cooling problem (in OEM setup) but in my mind a quallity problem ( plastik cracks ) No updated since.
Some of the radiators in your list looks for me same or similar only color or price is different.
Your Radiator from PWR look realy different. I dont know PWR - can you tell me more or give me a www url link ?
Thanks
That's the least of your worries. It'll be a long time before the plastic heat cycles enough time to crack. The bigger issue is, the OEM cores are so thin that they're easily damaged from rocks/debris hitting it during normal everyday driving. And it's a LOT of labor to replace it. I know; I've had this happen to me 3 times now.
https://www.pwrna.com/
I also was interested in the Modalworks setup, but their Stage 2 kit (with all 3 upgraded coolers) has been sold out/not available for MONTHS... https://modalwork.com/collections/w205-c63
https://www.pwrna.com/
I also was interested in the Modalworks setup, but their Stage 2 kit (with all 3 upgraded coolers) has been sold out/not available for MONTHS...
https://modalwork.com/collections/w205-c63 Seriously though huge difference, I have had my car for 8 years now and replaced the OEM coolers once then upgraded to the ModalWorks PWR coolers and never had a puncture since. My car now has over 50,000km with the PWR coolers on it and they have never let me down except for the "ModalWorks PWR" logo which has now almost vanished and faded away. If ModalWorks could send out a stencil to me I'd get them re-painted again. If not, I'll have to repaint them silver 🤷♀️
Here's a picture of how thick these PWR coolers are compared to stock
Last edited by Jimmy_c63s; Dec 24, 2025 at 02:53 AM.
Senior Member
Joined: Dec 2025
Posts: 423
Likes: 37
From: Keep it simple - keep it OEM
AMG C63s Coupe
The radiator OEM Plastic problem (smal radiator) … i read from two guys this story … had this problem too and get new oem radiator but after ~ a week same problem again then new oem radiator again. they told again issue plastic according to information from the workshop. i dont talk obout “stone” crack - leakage was on a area no stone can touch.
Sold out sounds not good … is no new delivery date known ?
Sold out sounds not good … is no new delivery date known ?
Last edited by C63s_Jack; Dec 24, 2025 at 03:20 AM.
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
10 Most Reliable Mercedes-Benz Models You Can Buy Used
Verdad Gallardo
Super Member
Joined: Oct 2015
Posts: 908
Likes: 133
From: Tampa, FL
'17 AMG S63 Convertible, '17 AMG C63S Edition 1 Coupe
Seriously though huge difference, I have had my car for 8 years now and replaced the OEM coolers once then upgraded to the ModalWorks PWR coolers and never had a puncture since. My car now has over 50,000km with the PWR coolers on it and they have never let me down except for the "ModalWorks PWR" logo which has now almost vanished and faded away. If ModalWorks could send out a stencil to me I'd get them re-painted again. If not, I'll have to repaint them silver 🤷♀️
Here's a picture of how thick these PWR coolers are compared to stock
Here's a picture of how thick these PWR coolers are compared to stock
