Ford F150 Forum - Community of Ford Truck Fans - 2011-14 F150 5.0L Coolant Leak Fixes

Having had my truck for a few years now, it seems like I have experienced every coolant leak there is. I will touch on my experience and combine the info that I have gathered to help make an all-in-one spot to find info on how to fix your trucks coolant system. My truck is a 2011 with 196,000Km. Most of my parts I try to get from RockAuto. I will not touch on hard parts, like the 90* top of block fitting (#BR3Z8592P) or the water pump, as these are pretty straight forward fixes that are usually just replaced.

Coolant Reservoir. The hose elbow of this unit is known to leak, with the suggested dealer route to replace the hose and bottle/airbox at once, as often times just the hose doesn't fix the problem. This costs usually north of $600 at the dealer. Pegasus makes a great kit with hose clamps and a 3/4" to 3/4" adapter to tie into the existing coolant line, you just cut off the quick connect to eliminate that failure point. I chose something similar and found a 1" ID (coolant tank fitting size) radiator hose with a 90* bend in it, and a stainless steel (brass works too) 1" to 3/4" double barbed fitting. This combined with 3 hose clamps has kept my system from leaking for about 22,000km now. If you do want to replace the OEM hose and tank, Dorman makes a replacement tank #603275 (I have not used it nor can I speak of quality), for $165 on Rock auto, and the OEM hose BL3Z8C350A for $22, which I suggest replacing as a pair.
Pegasus kit: https://www.pegasusautoracing.com/pr...sp?RecID=25905
My Route (mostly due to shipping costs into Canada from Pegasus): Napa 1" ID hose with 90* bend (any coolant hose with 1" ID works). Stainless 3/4"-1" OD Double barbed fitting. 3x stainless steel hose clamps, 2x 1" and 1x 1.25". Total cost, about $37 CAD.

(This section will talk about the upper radiator hose, Part # CL3Z8260A)
T connector. This connects to the top of the block through #BR3Z8592P, the Thermostat housing and the upper radiator hose, and is usually about a $70 part. The part number is DR3Z-8566-A, if your leak is on the upper radiator hose side (left), it uses rubber seal part # BC3Z-8590-F or the hose with seal is #CL3Z8260A. On the thermostat side, ford doesn't offer a part number for the seal, but it has been found by another member (Bobo.mo) to be a 4mm Thick x 31mm I.D. rubber seal. It is NOT the same seal as on the upper/lower radiator hose. Link to a suitable 4mm x 31mm seal here: http://www.theoringstore.com/index.p...73d99e98efdd19

Lower Radiator Hose. Part number BL3Z8286C can be had from Rockauto for $56. From what I have gathered, this hose also uses the same seal as the upper radiator hose, part number BC3Z-8590-F. As of yet this hose has not leaked for me, but if it does I will likely replace the whole hose as it is not a expensive part. You will need to drain your coolant system to replace it though, so don't forget to grab ford orange coolant.
Link: https://www.rockauto.com/en/moreinfo...0459&jsn=10459

Radiator. I had to replace mine due to a leak between the barbed fitting of the transmission cooler and the side tank of the radiator. I originally went with a Napa radiator (Spectra Premium), but found out after installing it that the lower radiator fitting has a tapered end, that is clearly cut on an angle. This DOES NOT SEAL to the lower radiator hose and as I found out, will dump your new coolant on the ground. I switched to an OEM ford radiator and am glad I did, I also noticed the Napa rad was bent from manufacturing and was of poor quality.
My OEM part number for HD cooling is BL3Z8005B. Standard cooling is BL3Z8005A. This can be bought at Rock Auto for about $179, and I highly suggest you go with OEM Ford. HD cooling are usually on 4x4 trucks with the tow package and AUX transmission cooler mounted in front of the AC condenser. NOTE, the AC condenser does NOT have to be removed/disconnected to do this job, but care should be taken when popping the old rad out and the new one in. Doing this below freezing temps increases the chance of breaking off something on the rad.

Heater Core. The part # is BL3Z18476A and it cost $88 on Rock Auto. Inlet pipe is #BL3Z18472B, Outlet pipe is #BL3Z18472G. The pipes are $30 each and I suggest if one is leaking to replace the whole hose. You will not need much coolant for this, so a single bottle of orange premix is enough. Be sure to prime/burp the system when you finish to get air out of the core with your heat on hot defrost.

Coolant. Our trucks take Ford Specialty Orange coolant. It is recommended to NOT mix coolants, as sludge of the system can form and the cost of the repair will FAR exceed the money you saved on coolant (think new rad, thermostat, block torn down to flush everything, new heater core). Oil, Tires and Coolant are 3 things to never cheap on, and I bought it unmixed for $23/bottle, and used 2 bottles to do my radiator and flush my system. Mix ONLY with Distilled water. I used an empty water jug, poured my coolant into the jug, then filled my orange coolant bottle to the same level with distilled water and poured that into the jug with the coolant, shake to mix and add the mix to the truck for a 50/50 mix at a lower price than Ford's Premix Orange. NOTE: the Ford orange coolant turns pinkish looking when mixed with water, so don't freak out if your truck doesn't look like it has orange coolant.

This should cover about 95% of the issues I have seen online regarding coolant leaks on our 2011 to 2014 F150 and Mustang 5.0L. Please feel free to add to this or post any questions or areas where I may be incorrect.

CRJ.