Autobox Lockup Mod Query

[Bogus]

Fit a separate ATF cooler, bypassing stock completely and then fit a radiator from a manual. Its my experience that the ATF does not contribute to adding heat to the engine jacket, quite the opposite in fact. I have never seen the ATF temp higher than the water temp. Usually its considerably lower. Ive pulled a 1500kg caravan up a couple of good hills now ( Slochd summit leaving Inverness on the A9) and the hottest I saw there was ATF 85, water 103. I have a separate ATF cooler with stock bypassed. My next step will be a new rad from a manual, giving a bigger surface area and removing the so called water flow obstacle. I,ll probably renew the water pump at the same time just for the hell of it, and aditional comfort.

[Surf01]

We are towing a twin axle caravan with MTPLM 1800kgs and so far no issues with over heating, however I did have the transmission fluid changed recently. Even before doing that we had issues towing up Fish Hill.

[BUSHWHACKER]

Fit a separate ATF cooler, bypassing stock completely and then fit a radiator from a manual. Its my experience that the ATF does not contribute to adding heat to the engine jacket, quite the opposite in fact. I have never seen the ATF temp higher than the water temp. Usually its considerably lower. Ive pulled a 1500kg caravan up a couple of good hills now ( Slochd summit leaving Inverness on the A9) and the hottest I saw there was ATF 85, water 103. I have a separate ATF cooler with stock bypassed. My next step will be a new rad from a manual, giving a bigger surface area and removing the so called water flow obstacle. I,ll probably renew the water pump at the same time just for the hell of it, and aditional comfort.

3rd gen auto rads aren't as restrictive as the 2nd gen's....
http://www.hiluxsurf.co.uk/showthrea...hlight=autopsy

[Bogus]

We are towing a twin axle caravan with MTPLM 1800kgs and so far no issues with over heating, however I did have the transmission fluid changed recently. Even before doing that we had no issues even towing up Fish Hill.

Do you have an idependent temp gauge or just the stock Toyota one? My stock one never so much as budged during my haul up Slochd, but the extra one went from 83 to 103 deg. Not a life threatening temp I know but a significant increase ( 24%). I dont know when the stock gauge will start to move but Im guessing there is fine line between OK and O My God.

[Bogus]

3rd gen auto rads aren't as restrictive as the 2nd gen's....
http://www.hiluxsurf.co.uk/showthrea...hlight=autopsy

Thanks for the reminder Prof, I had forgotten that thread. Its probably not worth changing a good rad in that case as there is little to gain. It was interesting to read that thread again and see all the comments regarding the size of the ATF cooler. My experience tells me that for normal out of town driving , with no stop /start motoring going on, the ATF cooler is actually a heater, which maintains the ATF at the same temp as the water.

[steved]

Most of the overheating problems on 3rd gen surfs are not caused by the transmission its high revs and low speed for a extended period so that the airflow into the rad drops that cause most of the issues, I have towed caravans up to 1600kg around France for a few years including up is the French Alps and up long climb out of Montpellier up on to the A75 without the gauge rising to far, the only time mine got hot was when the missus let me go up the Col Du Forclaz in the Surf on its own early one morning to book a Paracend flight the road was empty lots of hairpins and the back end was hanging out nicely and she was boiling when I stopped at the top, overheated the brakes on the way back down doing the same thing they certainly ain't a 2 ton rally car!
Keep the revs down and don't tailgate.

[boma23]

I think its fair to say that if styles of driving cause the overheating, then it's still fundamentally an issue with the cooling and heat dissipation of the car as whole. Bad rad & ATF cooler placement, stat and sender placement, size of torque converter... Etc. giving what's essentially a solid engine a bad rep.

My old Integra track car would belt round tracks all day long between 4-7.5k rpm, with maybe 180bhp from a NA 1560cc and never even think of getting hot.

But there again it couldn't crush slow moving pedestrians as easily.