Mishimoto Radiator user feedback

DavidNC

Founding Member
Sep 16, 2002
119
0
16
My Mishimoto radiator leaked after about 2000 miles driven in 16 months. Actually, I had suspected a leak a while back but it took being in a Christmas parade to know I had a leak. I put the pressure testes on it, and the coolant flowed out the leak.

I put my old stock radiator back on and wrote Mishimoto about covering it on "extended" warranty. It leaked on the lower passenger side tank area. It seems to me that this may be a defect in the design, since so many others have had a problem.

As far as cooling performance, it never seemed to cool any better than the stocker once I ran more than 30 miles. Both radiators worried me when driving the highway in 90 deg plus temps.
 
  • Sponsors (?)


Mustangs have problems with ALL radiators on the passenger side. This is a flex point for the chassis and under normal use the body twist will flex the radiator as well.

The radiator is held pretty tight to the radiator support by its brackets. A theory is the radiator is already under torque because the brackets are too tight. Some people have cut the rubber grommets on the radiator somewhat so the radiator is a bit loose when installed. No word on whether this makes the radiators last longer, though I'll be trying this when I install a new radiator.
 
It was a very tight fit, where as the stocker moves quit a bit.

If Mishimoto replaces it (this was my first replacement because the neck leaked out of the box), I'll probably go through the hassle of installing it. If not, I'll try my stocker (replacement with life-time warranty) and see how it does in summer. If it gets hot, I'll go with a summit universal radiator and set it in loose.
 
i installed my radiator in june and its leaking already.started 2 or 3 weeks ago.
i cut the rubber on the brackets but i guess it didnt help:(.
it looks to be leaking from both end tanks.
i need to see if my stock radiator can be fixxed,than i'll have the mishimoto replaced.

with the rubber cut,i can move the rad forward and back alittle,but up and down is still alittle tight.
 
just earlier today i noticed that my replacement mishimoto is leaking...i put about 600 miles on this one and the previous one i had for about 1500 miles

i dont think i'll be taking them upon their warranty again...i want my $$$ back:notnice:
 
...any suggestions on a GOOD & RELIABLE radiator for our cars?

cooling is really not something i wanna mess with and keep re-installing faulty parts, i wanna know that everything is up to par and functioning properly

im debating going back to a stock replacement rad. Any feedback on those?
 
making room for movement is a good idea since the aftermarket ones are going to be a tad larger.

To those that have leaks...anyone have full length sub frame connectors? I wonder if that helps with the flex? Looking at the mod list it looks like most of you dont have subs...might help the issue.
 
...any suggestions on a GOOD & RELIABLE radiator for our cars?

cooling is really not something i wanna mess with and keep re-installing faulty parts, i wanna know that everything is up to par and functioning properly

im debating going back to a stock replacement rad. Any feedback on those?



You can spend $200 on a Mishimoto and have it leak or spend $400 on a fluidyne and that is just as likely to leak.

I agree that the tight fit and the body flex of our cars has a lot to do w/ it. I took mine to the track quite a bit after it was installed and I figured if anything that would cause it to leak b/c of the load and twisting the car is subjected to.

One thing that has not been documented is what kind of chassis stiffening is done for the ones that leak and the ones that dont. I have a good Strut Tower brace, full length sub frames and a 4 pt cage, needless to say the car does not flex much.
 
I led up the group buy and have not installed mine yet!! Its been about a year so I have to get it in this spring.:) Too many other projects!!:rolleyes:

The car I'm putting it in has from Saleen a 3 row high flow copper brass. There is no way a stock replacement skinny radiator would keep this car cool in hot weather.

For those with stock engines I'm sure that a stocker will work for you. On a side note my son's 95 GT has gone though a stock radiator and the stock replacement lasted 8 months before it started to leak on the plastic tanks. So it's not just aftermarket radiators that have problem's.
 
I am currently on Mishimoto number 3. I was a part of the original group buy, and i think mine started to leak in less than 4 mos. They replaced it and i threw it on. Everything was cool, until June of this year, about 16 mos. after second one. Again the radiator started leaking.

I called KTeller and told him about them about the issues. He said that Mishimoto was no longer working with them, and to email Mishimoto directly. When i emailed them, i received an email fairly quickly explaining that they had redesigned the old radiator, and made it a 3 row radiator. Even though my warranty was up, they sent me a knew one, and just asked for a picture of my old leaky one. So far, so good. I am going to try to stiffen up the chassis of my car, hopefully that will help as well.