TTORA Forum banner
1 - 1 of 1 Posts

Premium Member
12,213 Posts
Discussion Starter · #1 ·
My truck has had issues keeping itself cool. Completely empty on the freeway it would run 198-200, up a slight grade, I'd be pushing 205-210. While towing my boat, A/C off, up a slight grade, I hit 219, and the fan clutch wasn't even engaged. These temps were read thru scangauge, and note that the gauge on the dash was in the middle the whole time.

Check this link out. The Landcruisers have problems running hot, and this info applies to the Stock AISIN clutch...

I did not change the silicone fluid, but I will probably at some point change it to 6,000 CST fluid.

I checked my "timing" on the clutch. The hole would be halfway open when I heated the water to 137 degrees. I adjusted it so the hole is halfway open at 107 degrees. Note that this is not engaging the clutch 100%, this is when the clutch starts shearing some of the oil.

I immediately noticed that day that the A/C is much cooler, especially at stoplights. Around town my truck now runs 188-190 degrees, on a hot day, with the A/C running. With the a/c off, the temp is the same.

On the freeway, loaded for a 4 wheeling trip (roughly 400-500 lbs extra) the truck runs about 192 on the freeway, climb a grade and the temp still climbs. I went up this long grade doing 70, 4th gear pinned (to see how hot I could get it up to) and the temp spiked slowly to 209. Once I was flat, the temp cooled off much quicker than it used to, back to 192.

Crawling the trails, you can hear the fan, where before you would never really hear it at all. All day crawling with the AC on, the hottest I got was 193, before I'd be in the 200 degree range and the A/C would be cool. The A/C is now cold.

I wouldn't recommend the 10,000 CST fluid, and the 95 degree engagement, but I would recommend a 6,000 fluid changeout, and around a 107-110 engagement.

FWIW, changing the engagement just makes the fan come on sooner. The amount of fluid and the thickness of the fluid makes the fan clutch spin faster when engaged. Also note that a fan clutch will never be 100% engaged. There will always be some slip. At "full engagement" you're probably still slipping 5-10%...

Either way I'm happy. I saw no loss in MPG's, and the motor and PS pump is now kept cooler. Cost me no money, but if I were to change the oil, I would be out only about 10 bucks :)
1 - 1 of 1 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.