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Duramax LML Coolant Bypass Kit 2011-2016 Duramax Diesel 6.6L

Duramax LML Coolant Bypass Kit 2011-2016 Duramax Diesel 6.6L

SKU: JCGbypass

This John C Garage coolant bypass kit is the ultimate combination to prevent any headaches or leaks down the road on your off-road 2011-2016 Duramax LML. We pride ourselves on having this kit in stock and ready to ship at all times! 


It’s very common that we see the black or blue coolant hoses from other solution kits come apart at the crimped end or the hose ripping apart leaving you with a huge coolant leak and stranded. Take a look at the 2nd photo for example of these cheaply made hoses that this kit replaces entirely. If you have experienced a leak with yours, here is your fix! This kit offers a more robust coolant routing and components.


You will need to remove the down pipe to gain access to the coolant plug on the rear of the engine (5th photo) so we highly suggest replacing it with a full 3" down pipe if you do not have an aftermarket down pipe already. The 3" down pipe fits much better than the factory down pipe making it easier to install. The down pipe we offer in the drop down option can be viewed here by itself. It is from Wehrli Custom Fab and is the stainless steel version. Click here


**Down pipe selection!** For the 2015 LML Duramax, be sure to physically look at which downpipe you need! It could be either the vband (11-15) or if it has 3 bolts at the connection, it's (2015-2016). If unsure, send us a picture and we'll be able to tell which you need!


Here is the upgraded coolant block off plate we suggest doing at the same time as the coolant bypass kit which can also be viewed on the last photo of this listing. Click here


LML Coolant bypass hose

Duramax LML coolant hoses

LML leaking coolant

Duramax LML coolant hose fix

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