I searched through the forum and cound not find an answer. Any guidance will be much appreciated!

There are two types of thermostat on Atlantic British:

Thermostat Discovery II (Genuine Part # PEM100990) - Land Rover cooling/heating from Atlantic British
Land Rover Discovery II Replacement Thermostat

The first one is the geniune LR part. I believe this is the 195-degree version. I bought the second one which is listed as the "warm weather climate" version. I believe this is the forum recommended 180-degree version. Am I correct in my assumption?

Any thoughts on the type of coolant?

Thanks!!!

 

Land Rover has a genuine version of both, but yes you want the 180 degree version. Test it before you install it.

 

I just bought the motorad 439 180 very happy with it I got tired of the confusion of the atlantic British site and even their customer service reps had no idea which one I was trying to order
Go with the motor rad 439 189 amazon has them and get an ultra gage best bang for the buck for our trucks

 

Also, if you are replacing the t/stat and are running DexCool, replace your coolant pressure cap because they also fail.

 

You want PN PEL500110. Be sure it's the genuine and not a knockoff, there have been several reports of BP Utah selling motorad rather than genuine. Some others may also.

 

The biggest sign is that the Genuine will be GREY and not white/offwhite color.

THERMOSTAT ASSY DII & FREELANDER 180° F, PEL500110, RNQ028 - Land Rover Parts | Rovers North

 

The 180 PEL that Atlantic British sales is a Motorad. RoversNorth sales the Genuine 180 Grey Thermostat.

 

I just noticed that and contacted him to correct the wording was a simple mistake on his part. I recently bought one from him, yes it is a Motorad 180, which used to be grey but is now white and stamped Motorad on the side of it. I believe that is the same with the one from Rovers North.

 

RN does not carry any Motorad thermos, we also only carry one version of the PEL500110, the Genuine grey one. Not knocking the motorad, a lot of people have had them work quite well. We just do not carry them. We do however have an aftermarket version of the PEM regular thermostat.

 

Yep and yes sir.
I put in the grey one - 180 degree.
Single best thingyou will replace.

The thermal cycling will go down a bit and the heads will not expand and contract so much with the huge 30 degree temp swings with the stock thermostat.