Coolant for 2008, OM642

Messages
283
Location
England
Hi Gents. Which Coolant to use for a Merc' OM642 3.0crd in a 2008 Jeep Grand Cherokee? Should I use a G05 HOAT as suggested by Jeep or a G05 as suggested by Mercedes? Does it indeed matter? At the moment my coolant is orange if that is of any relevance at all. Many thanks. Tikka.
 
Messages
2,235
Location
Lyndhurst NJ
Id match the Orange from Jeep, the coolant is blue for most Mercedes like my GL320, so unless you can get all of it out, you my have some mixing.
 

Tikka

Thread starter
Messages
283
Location
England
Hi My Jeep Dealer says they now use this fluid and not a HOAT in my WK https://extranetpli-eu.pli-petronas.com/dsp/pdf/eng/stec/2241_stec_ENG.pdf I noted it was Blue and had the MB325.0 approval. Not sure how relevant that is. I can get a HOAT https://www.commaoil.com/passenger-vehicles/products/view/354 but this is clear Yellow. I can source Red coolants but they all tend to be OAT. As long as it is all thoroughly flushed and the correct type is used does coolant colour matter? Many thanks. Tikka.
 
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Tikka

Thread starter
Messages
283
Location
England
I will clarify things by saying that Jeep originally specified HOAT back then for the 2005-2010 WK.
 
Messages
196
Location
Europe
Here are the recommended coolants by MB https://bevo.mercedes-benz.com/d/d/en/Spec_310_1.pdf I believe the engine had 325.0 ex-factory .Might have been the analogue of G05 ("Glysantin G05 contains a corrosion inhibitor package with nitrites, borates and silicates. Glysantin G05 is free of amines and phosphates" -BASF description). Later G05 disappeared from 325.0 approval list (G48 is the favorite now...it lacks the nitrites but still has borates). Both G05 and G48 are HOAT liquids. Once upon a time both G05 and G48 were 325.0 approved: http://up.picr.de/7684380arn.pdf ...and were the only approved options for passenger car engines. OAT fluids were recommended for commercial engines along with HOAT fluids. Petronas Akros Farm Flu that your dealer uses is HOAT (it has borates too). .... In addition, G05 lacks 2-EHA in its formulation. Tikka ,have a look at Table 1.1 in the first .pdf (recommended specifications for PC engines)..then check 325.0 or 326.0 ...and 325.6 and/or 326.6 fluids in this list https://bevo.mercedes-benz.com/bevolisten/bevo-sheets-sort1.html ...and make your choice. I'd probably get a 325.0 G05 . Still widely available. This is an interesting read: https://www.mbca.org/sites/default/files/antifreedec04_0.pdf
 
Messages
1,054
Location
WV
I have an 08 642 and was talking to my Mercedes Indy mechanic a few days ago. I asked and he verified that Zerex Z-05 antifreeze is the proper one to use. It is light golden. The stuff in my ML at present is gold in color. My service book says to replace coolant every 15yrs. or 150k miles.
 
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