Vz v8 temperature drops going down hills

[Brian MacArthur]

I have just had a new radiator installed last week in my v8 auto SS. The temperature usually sits at the second bar from bottom of cold. It has started dropping to the 1st bar after traveling after 15 minutes when going down hills only, then comes back to below quarter on the gauge. The radiator is full as is the resorvior plastic tank. What causes this? Is running cool never goes above quarter on the gauge. I replaced the radiator after developing a crack on the plastic tank, it has never overheated. Could it be thermostat if so, why?

 

[Benboy]

When the car is going down hill, little if any load on the engine as a result the temperature drops. All perfectly normal.

 

[Eevo]

same happens in my vy.
its normal.

happens in most cars
European cars handle it better due to the way their plumbed up.

 

[vc commodore]

No load on the engine, nice cool air blowing into the radiator and engine bay = lower water temperature when going down hill

 

[MY18VF2SV6TTAN1C]

Would you prefer that it over heated?

 

[Munz]

Would you prefer that it over heated?

lol :nutkick:

 

[lowandslow]

My Monaro does this ever since i had the radiator replaced after the original split. In the summer time it gets to and stays at operating temp fairly quickly but in winter it can take nearly 20min of normal driving to get it upto temp on the gauge. Coast down a hill and the gauge can go to almost cold. Seems strange the thermostat would pack it in at exactly the same time as a radiator...

 

[Brian MacArthur]

I have just had a new radiator installed last week in my v8 auto SS. The temperature usually sits at the second bar from bottom of cold. It has started dropping to the 1st bar after traveling after 15 minutes when going down hills only, then comes back to below quarter on the gauge. The radiator is full as is the resorvior plastic tank. What causes this? Is running cool never goes above quarter on the gauge. I replaced the radiator after developing a crack on the plastic tank, it has never overheated. Could it be thermostat if so, why?

It's been 4 months since I replaced my radiator, it now has started leaking at the bottom of the plastic tank, similar place to my last new radiator that lasted 3 months? The car has never gone above 1/2 on the gauge. This is my 3rd radiator in 12 months why do they keep cracking...each radiator is from a different supplier & brand...what do I do??? I don't want to buy a ford

 

[figjam]

The replaced radiators.....were they second hand, reconditioned, or new ?
Did you fit them yourself or get professionals to do it ?
Is there something physical putting stress on the radiator body, mounting points ?, bent panel ? rubbing on some other other part ?

If they were professionably fitted, why not ask them why they are failing, and getting a warranty replacement.

 

[vr304]

You can get a full alloy radiator for a bit extra than a regular one.... No more plastic tanks to crack