GrimmSpeed 160 Degree Thermostat

Part #: GRM 068001
MSRP: This Item is no longer available.


Brand: Grimmspeed
Gasket Included: Yes
Opening Point: 160°F
Mfgr. Warranty: 2 years
Return Policy:

RallySport Guarantee - 30 Days

Items that are covered under the RallySport Guarantee offer a 30 day no questions asked return policy.

RallySport Guarantee items may be returned within 30 days of the original invoice date and must include all the original parts and contents for a refund.

The RallySport Guarantee does not apply to products that have been modified, damaged, misused or abused. All returns require an RMA (Return Merchandise Authorization) Number, and freight charges are strictly non-refundable. For more information regarding our freight refund policy, please refer to our return policy page found HERE.
RallySport Guarantee


First rule of thumb, excess heat kills engines and power. GrimmSpeed is on your side with their 160 Degree Thermostat. This thermostat will make an immediate and direct impact on your engine running temps. The 160 Degree T-Stat will bring your engine coolant temps down 20-30 Degrees.

Many OEM style T-Stats can have a very negative effect on your vehicle, if they fail, they fail closed and your car will overheat. But not Grimmspeeds! If there is a failure with the T-Stat, it will fail in the OPEN position allowing coolant to flow and keep your engine temps under control.

Given the fact most Subarus are turbo'd, this gives you even more of a reason to want to keep those coolant temps down. In turbo'd applications, the engine coolant must also cool the turbo and the engine oil. This places a greater strain on your oem thermostat...all the more reason to install the GrimmSpeed 160 Degree Thermostat!

During testing, Grimmspeed has also found that their 160 Degree Thermostat keeps the engine coolant at a more stable temperature.

REVIEWS ( 14 )


Verified Purchase
Great Product!!
redwrx0545381 2 years ago
This is a good quality product, but i had an issue with it fiting into my new Gates waterpump. Turns out the Gates water pump had some left over casting slag that wasnt machined properly and this caused enough of a clearnace issue that it wouldnt seat properly. So i went with a factory one and it fit perfect. Just a heads up... I would have ground out the small portion on the pump but it was already installed on the car.
Verified Purchase
Failed in less than a year
JLD13 2 years ago
Installed in March of 2013 and worked fine through spring and summer of 2013. It worked like a thermostat should - it did it's job. Then six months after my purchase I noticed that if I was cruising in 5th gear my temp would go low. As winter approached the heat in my car wasn't great and the temp would be very low. It's December now and during a cold spell my car wouldn't warm up at all. Turns out this tstat failed. I just replaced this with a stock Subaru unit. The one saving grace is that these fail in an open position.
Verified Purchase
Car was overheating
DaveinNorCal 3 years ago
Chasing an overheating problem. Car has good compression and no head leaks, but an aggressive tune was giving me fits. I installed this and removed OEM and its been awesome. If nothing else, it's made the car stable enough to drive in traffic while we hunt for a deeper problem. Temps are right in the normal zone and drop into the 170's on the freeway.
Verified Purchase
easy install
Fanooch28110 3 years ago
very easy to do. anyone can do this. just put jiggly breather thing to the top and slip in to place. i didn't notice any change on gauge but I'm sure its doing its job.
Verified Purchase
Does the job
favergarav 3 years ago
Good product, and does the job. You can really tell if it does anything with the stock gauge of temp, I could see a drop in temp in about 5-10 C° after I installed.


  • AnswerQ: Dyno  s20525xxx 3 years ago

    Do I need a retune after install this? Thanks.

    • A: No tune is necessary to install this part. Mike

      GrimmSpeed 3 years ago

  • AnswerQ: install difficulty  wrmyx08 3 years ago

    How hard is this to install yourself? do you have to Bleed the radiator? what would you say is the average install time

    • A: If you're familiar with the system you can have the whole thing done in about 30 minutes. You will have to drain and fill the coolant. Mike

      GrimmSpeed 3 years ago

  • AnswerQ: Direction  jtanner6238883297 4 years ago

    I notices on some thermostats there is an up symbol and this does not have one, is there a certain way this thermostat has to be placed in the pump like is there a too a bottom to it?

    • A: Hey! Our thermostat has a breather that you can see in some of the pictures. This is to be the top of the thermostat to allow any air to travel past. Mike

      GrimmSpeed 4 years ago

    • A: Let me redo this question. On the GS thermostat there isn't an up symbol like other thermostats to tell you which direction to place it. I was wondering of there is a top and bottom to the GS thermostate or can you just install it in any direction.

      jtanner6238883297 4 years ago