GL Class (X164) 2007-2012: GL320CDI, GL420CDI, GL450, GL550

Choosing replacement radiator

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old Dec 10, 2021 | 03:21 PM
  #1  
eric_in_sd's Avatar
Thread Starter
MBWorld Fanatic!
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2010
Posts: 2,742
Likes: 627
From: Emmett, ID, USA
2007 GL450
Choosing replacement radiator

Rock Auto currently has three, with a range in prices from $140 (CSF) to $170 (Nissen) to $240 (APDI/PRO).

The cheap one has glass reinforced plastic while the expensive one has plastic reinforced with glass.

I am inclined to not skimp on such a mission critical component, but was curious what experience y'all have had with the various brands. I always thought of a radiator as a lifetime component, but plastic and aluminum ... I guess not.
Reply
Old Dec 10, 2021 | 05:34 PM
  #2  
DennisG01's Avatar
MBWorld Fanatic!
5 Year Member
 
Joined: May 2015
Posts: 1,932
Likes: 291
From: Allentown, PA
'08 GL 320 CDI
The terms they used are the same thing - just worded differently. However, Glass Reinforced Plastic (GRP) is the proper term... AKA fiberglass. FRP ends doesn't worry me one bit. Generally radiators can last a bit longer - but 15 years isn't all that bad, either.

I'm not familiar with the $140/$240 ones - have only heard of Nissens. Never really heard anything bad, though. However... go to FCP - see if they have a Behr unit. Anything you get there also has a lifetime warranty.
Reply
Old Dec 11, 2021 | 11:08 AM
  #3  
eric_in_sd's Avatar
Thread Starter
MBWorld Fanatic!
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2010
Posts: 2,742
Likes: 627
From: Emmett, ID, USA
2007 GL450
Originally Posted by DennisG01
The terms they used are the same thing - just worded differently. However, Glass Reinforced Plastic (GRP) is the proper term... AKA fiberglass. FRP ends doesn't worry me one bit. Generally radiators can last a bit longer - but 15 years isn't all that bad, either.

I'm not familiar with the $140/$240 ones - have only heard of Nissens. Never really heard anything bad, though. However... go to FCP - see if they have a Behr unit. Anything you get there also has a lifetime warranty.
One of them is a "glass-fiber plastic composite". I guess you're going to try to tell me that's the same thing as well!

Good tip on FCP Euro. I always forget about those guys.

The pain about the radiator is you can't tell where exactly it is leaking. Any drips run along the front rail, or at least that is the impression I am getting.
Reply
Old Dec 11, 2021 | 11:14 AM
  #4  
eric_in_sd's Avatar
Thread Starter
MBWorld Fanatic!
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2010
Posts: 2,742
Likes: 627
From: Emmett, ID, USA
2007 GL450
FCP Euro has the Mahle/Behr:
https://www.fcpeuro.com/products/mer...tor-2515000303

About the same price as the ADPI. Seems like an easy choice.

The radiator might not even be leaking. Hard to tell with how it is recessed.

Last edited by eric_in_sd; Dec 11, 2021 at 11:30 AM.
Reply
Old Nov 20, 2023 | 08:58 AM
  #5  
texas008's Avatar
Senior Member
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Apr 2014
Posts: 332
Likes: 70
2007 GL450
Originally Posted by eric_in_sd
FCP Euro has the Mahle/Behr:
https://www.fcpeuro.com/products/mer...tor-2515000303

About the same price as the ADPI. Seems like an easy choice.

The radiator might not even be leaking. Hard to tell with how it is recessed.
did you replace your radiator? how hard is it? I hope there is no need to remove the AC condensor together with the radiator (shown in one youtube video).

Reply
Old Nov 20, 2023 | 09:34 AM
  #6  
eric_in_sd's Avatar
Thread Starter
MBWorld Fanatic!
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2010
Posts: 2,742
Likes: 627
From: Emmett, ID, USA
2007 GL450
Originally Posted by texas008
did you replace your radiator? how hard is it? I hope there is no need to remove the AC condensor together with the radiator (shown in one youtube video).
Yes, I did replace the radiator. It was not all that difficult of a job. It is tedious, though. You do not need to remove the condensor.

My recommendations:

First, confirm that the radiator is in fact leaking. I mistook Pentosin power steering fluid for coolant, and did not realize the lower heater hose was slowly leaking. Rule out other possible causes. If the coolant has been properly maintained, the only reason to expect the radiator to leak is o-ring failure, which does happen, but generally only manifests when the o-ring is disturbed. The upper radiator hose is notorious for this; the o-ring grows and cannot be reused.

As with similar repairs, there is a lot of "while we're in there". If you have not, replace the radiator hoses, including the bottom heater hose, although that one is fairly easily doable with the radiator in place. Replace the spring type hose clamps with screw drive. The power steering low pressure lines can also be replaced. Mine had begun leaking, which caused the lower heater hose to fail.

I ended up customizing a fair amount of the flange that helps direct air in. I got rid of the entire bottom section, because I couldn't figure out how to get it back in. I also eliminated a few of the bolts that are hidden in weird places. The engineering of the body related work is just weird. I took off the underbody panel that covers the TPMS antenna; there were nine (9) bolts attaching the heat shield to it. This is four more than WIS shows. One bolt never caught the clip nut threads again, I have not checked whether it fell out on its own. Another bolt, I could never figure out where it went. It joined its friends in my M6 bolt bucket. In general, when I work on the GL, parts and fasteners are left over.
Reply
Old Nov 20, 2023 | 09:50 AM
  #7  
texas008's Avatar
Senior Member
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Apr 2014
Posts: 332
Likes: 70
2007 GL450
Originally Posted by eric_in_sd
Yes, I did replace the radiator. It was not all that difficult of a job. It is tedious, though. You do not need to remove the condensor.

My recommendations:

First, confirm that the radiator is in fact leaking. I mistook Pentosin power steering fluid for coolant, and did not realize the lower heater hose was slowly leaking. Rule out other possible causes. If the coolant has been properly maintained, the only reason to expect the radiator to leak is o-ring failure, which does happen, but generally only manifests when the o-ring is disturbed. The upper radiator hose is notorious for this; the o-ring grows and cannot be reused.

As with similar repairs, there is a lot of "while we're in there". If you have not, replace the radiator hoses, including the bottom heater hose, although that one is fairly easily doable with the radiator in place. Replace the spring type hose clamps with screw drive. The power steering low pressure lines can also be replaced. Mine had begun leaking, which caused the lower heater hose to fail.

I ended up customizing a fair amount of the flange that helps direct air in. I got rid of the entire bottom section, because I couldn't figure out how to get it back in. I also eliminated a few of the bolts that are hidden in weird places. The engineering of the body related work is just weird. I took off the underbody panel that covers the TPMS antenna; there were nine (9) bolts attaching the heat shield to it. This is four more than WIS shows. One bolt never caught the clip nut threads again, I have not checked whether it fell out on its own. Another bolt, I could never figure out where it went. It joined its friends in my M6 bolt bucket. In general, when I work on the GL, parts and fasteners are left over.
Thanks a lot for the tips. will need to check where the leak spot is. currently my GL450 loses about 500 ml of coolant for every 1k miles.
screw drive clamps are readily available and easier to work with. however sometimes the spring hose clamps are preferred since it will not get loose.


Reply
Old Nov 20, 2023 | 10:28 AM
  #8  
eric_in_sd's Avatar
Thread Starter
MBWorld Fanatic!
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2010
Posts: 2,742
Likes: 627
From: Emmett, ID, USA
2007 GL450
It is probably largely a matter of personal preference. I never had screw type clamps come loose, and they are vastly easier to service in place, especially in cramped quarters.
Reply
Old Nov 20, 2023 | 10:42 AM
  #9  
texas008's Avatar
Senior Member
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Apr 2014
Posts: 332
Likes: 70
2007 GL450
Originally Posted by eric_in_sd
It is probably largely a matter of personal preference. I never had screw type clamps come loose, and they are vastly easier to service in place, especially in cramped quarters.
could use some blue locktite on the screws just in case.
Reply
Old Nov 20, 2023 | 10:57 AM
  #10  
eric_in_sd's Avatar
Thread Starter
MBWorld Fanatic!
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2010
Posts: 2,742
Likes: 627
From: Emmett, ID, USA
2007 GL450
Originally Posted by texas008
could use some blue locktite on the screws just in case.
I really doubt the screw backs out, given that it is under tension from the compressed hose walls. However, that illustrates a potential failure point: The rubber of the hose walls loses elasticity over time. The spring type clamp provides springiness even as the hose stiffens.

I believe the auto manufacturers use spring clamps almost if not entirely as a cost and labor savings measure.

For what it's worth, I forgot entirely to install one hose clamp and was surprised to find it did not leak during idle warmup. So the clamps do less than you might think!

By the way, I recently had to polish down casting seam marks on the radiator inlet plastic. It is infuriating that a supposed high quality (Mahle) radiator, they can't even make the moulds better or polish the plastic. I suggest going over all the fittings before you install a new radiator.
Reply
Old Nov 21, 2023 | 08:39 AM
  #11  
texas008's Avatar
Senior Member
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Apr 2014
Posts: 332
Likes: 70
2007 GL450
Originally Posted by eric_in_sd
FCP Euro has the Mahle/Behr:
https://www.fcpeuro.com/products/mer...tor-2515000303

About the same price as the ADPI. Seems like an easy choice.

The radiator might not even be leaking. Hard to tell with how it is recessed.
This Mahle Behr radiator is no long available at FCPeuro.
the remaining options are
CSF 3457: $146
CSF 3458: $151
Genuine Mercedes : $309

wonder is there is any suggestions/hint about the options. Thanks,




Reply
Old Nov 21, 2023 | 01:30 PM
  #12  
Max Blast's Avatar
MBWorld Fanatic!
15 Year Member
Photogenic
Loved
Community Favorite
 
Joined: Jan 2010
Posts: 3,101
Likes: 779
NGL450 w/EORP, S550
Not to shill but auto house AZ now has free shipping for everything under hundred pounds, but over $150
Reply
Old Nov 21, 2023 | 01:45 PM
  #13  
texas008's Avatar
Senior Member
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Apr 2014
Posts: 332
Likes: 70
2007 GL450
FCP euro has free shipping too, and 10% off $400 purchase.
Reply
Old Nov 21, 2023 | 03:01 PM
  #14  
eric_in_sd's Avatar
Thread Starter
MBWorld Fanatic!
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2010
Posts: 2,742
Likes: 627
From: Emmett, ID, USA
2007 GL450
In my experience, when FCP Euro does free shipping, they drop ship. So you may wait quite a while.

But in any event, FCP Euro is about the same price as Rock Auto.

It looks like the market for gourmet radiators, e.g. Mahle/Behr, has dried up. Maybe they figured out they just weren't cost competitive. I guess it is not too difficult to make good radiators. My Mahle/Behr experience was not positive; the drain plug o-ring self disassembled (note they now sell replacement drain plugs!) and as I commented elsewhere, I had to polish the inlet to stop a slow leak.
Reply
Old Jul 12, 2024 | 07:54 PM
  #15  
lkchris's Avatar
MBWorld Fanatic!
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2005
Posts: 6,184
Likes: 241
From: Albuquerque
'10 CL550, '12 GL550
Originally Posted by eric_in_sd
I believe the auto manufacturers use spring clamps almost if not entirely as a cost and labor savings measure.
a lot of people believe that, but the fact is Oetiker, CLIC, etc., clamps tighten to a known value, whereas who knows with screw type clamps.

The WIS procedure for replacing the fuel filter on OM642 diesels expressly prohibits use of screw type clamps.

i think with ‘merikun iron, it indeed usually is cheapskatery, but with German stuff it’s engineering.
Reply
Old Jul 12, 2024 | 09:53 PM
  #16  
GL500 x164's Avatar
Junior Member
Liked
 
Joined: Jun 2024
Posts: 19
Likes: 8
GL500 x164
In my extensive forums research (merc, bmw, lexus etc), i found the Nissens to be the recommended replacement.
Also, i saw a video yesterday that stated the spring type clamps are necessary for plastic radiators due to thermal expansion as they can expand to apply constant pressure and to never use worm drive clamps as they are fixed and don't self-adjust. I'd prefer worm drive for ease of use but the explanation/demonstration made the disadvantage very clear cut.
Reply
Old Jul 13, 2024 | 09:55 AM
  #17  
BlownV8's Avatar
MBWorld Fanatic!
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Aug 2003
Posts: 8,881
Likes: 1,211
From: In my garage
E55, GLS450, GL63, GLE350
Well, the stock one is terrible so anyone but OE.
Reply
Old May 19, 2025 | 09:28 PM
  #18  
BlackML550's Avatar
MBWorld Fanatic!
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2014
Posts: 1,084
Likes: 440
From: Melbourne, Australia
2010 ML550 VIN WDC1641722A564750, 2010 B180
Hi,

I'm about to replace my radiator on my W164 with the M273 5.5 lt V8 - same leak and problem as described here. I've bought a new Mahle radiator (being delivered) but will I need to seperately buy seals for transmission lines and or power steering lines as well? I would have thought so. There's also mention of 'O' rings for the radiator hoses. Were they addtional orders as well or do the 'O' rings come with a a new radiator hose? I don't want to rip this thing out only to find I'm short parts. TIA
Reply
Old Nov 27, 2025 | 06:15 AM
  #19  
bloxham's Avatar
Junior Member
Liked
 
Joined: Jul 2024
Posts: 49
Likes: 10
From: UK, Oxfordshire
C350 NA
Radiator

My C350 with M276 looks like the radiator is weeping, so going to fit a Nissens replacement.
The radiator includes a transmission fluid cooler.
I'm thinking I can just replace any lost ATF by refitting the lower transmission cooler hose then filling the cooler with ATF with a syringe before refitting the upper Transmission cooler hose.
Have I got that right ?
Yes I could adjust the level at the transmission sump but that's a lot of extra work.
Thoughts ?
Reply
Old Dec 7, 2025 | 07:41 AM
  #20  
C230 Sport Coup's Avatar
MBWorld Fanatic!
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2002
Posts: 7,257
Likes: 168
From: So. Oregon Coast
C230 Sport Coup + 2006 W164 ML350 + 99 Ford Escort RIP
Behr is now made in China like all Meyle stuff. Junk.
I had replace a radiator recently on W203. Nissens.
REAL PIA on Kompressor. Had to remove the bumper and intercooler.
Reply

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -4. The time now is 07:36 PM.