I've gone back and forth with myself wether to make this post, yes I know people talk crap about MMR so I'm going to share my experience.
I purchased an MMR 1500 5.4 short block fully assembled with all the extras that were available, in my dealings with them I dealt with Brett who was fantastic, the motor was assembled and delivered before schedule everything looked absolutely perfect. I was putting 5.8 heads on a 5.4 block I was told that I had to use 2007 to 2009 head gaskets.
The motor was completely assembled everything went together flawlessly, I put about 250 miles on the set up and the first time I go into boost it pushes all the coolant out of the overflow tank, I was informed by another member on here that perhaps I have the incorrect head gaskets and that I need the 5.8 head gaskets because the combustion chamber is larger. Well, lo and behold that was the case after disassembling the motor MMR sold me, I find incorrect head gaskets. I called them to tell them of my findings and they argued the fact with me and told me that it was my tuners fault although the motor works flawlessly, obviously I have the incorrect gaskets based on poor information given by them. So, I'm paying to have the motor torn down and buy new head gaskets and do everything all over again based on incorrect information from them. They will do nothing to help me they just point the blame at my tuner. They seemed extremely helpful until I told them of the situation, now all I get is pointed fingers in the worst possible direction. In my phone call to them one of the guys at the shop said that they would gladly sell me the 5.8 head gaskets at a discounted price. Why would they offered to sell me head gaskets they believe are incorrect? My guess is they don't actually know what it takes to build the set up. My post is not to slam, slander or cause any other issues than state my experience with their lack of help.
I purchased an MMR 1500 5.4 short block fully assembled with all the extras that were available, in my dealings with them I dealt with Brett who was fantastic, the motor was assembled and delivered before schedule everything looked absolutely perfect. I was putting 5.8 heads on a 5.4 block I was told that I had to use 2007 to 2009 head gaskets.
The motor was completely assembled everything went together flawlessly, I put about 250 miles on the set up and the first time I go into boost it pushes all the coolant out of the overflow tank, I was informed by another member on here that perhaps I have the incorrect head gaskets and that I need the 5.8 head gaskets because the combustion chamber is larger. Well, lo and behold that was the case after disassembling the motor MMR sold me, I find incorrect head gaskets. I called them to tell them of my findings and they argued the fact with me and told me that it was my tuners fault although the motor works flawlessly, obviously I have the incorrect gaskets based on poor information given by them. So, I'm paying to have the motor torn down and buy new head gaskets and do everything all over again based on incorrect information from them. They will do nothing to help me they just point the blame at my tuner. They seemed extremely helpful until I told them of the situation, now all I get is pointed fingers in the worst possible direction. In my phone call to them one of the guys at the shop said that they would gladly sell me the 5.8 head gaskets at a discounted price. Why would they offered to sell me head gaskets they believe are incorrect? My guess is they don't actually know what it takes to build the set up. My post is not to slam, slander or cause any other issues than state my experience with their lack of help.