Radiator Outlet Temp Doesn't Change | 05 L322 4.4 M62

Yeah the temps scare me a little to be honest, the previous owner had the car overheat with loss of coolant at some stage (head off rebuild). Not sure if he nailed the root cause which is why I'm making sure shes in tip top.

When this thermostat arrives (Behr 2.548.88) I'll be doing a full flush w/ Nulon Flush & Clean + new OEM BMW coolant. So I'll report back numbers after. I think a trans pan drop, filter and refill is in my future too. I feel like the trans oil could possibly be a bit cooked. Oil has 30,000k on it currently, but at 115deg it would have degraded quickly.

PS, if anyone is looking for a place to get BMW/M62 parts, I use Clickable Automotive. I've been using them for years for my BMW. 10/10 shop. BMW coolant is $15 a bottle (1.5l) which is 50% of the dealer cost.

Australia's online BMW parts specialist | Clickable Automotive

Stay safe!

Reuben

Quote:

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Originally Posted by FisherX

(As far as I'm aware the standard thermostat is 115 deg with a electrical override switch for high load conditions. I'm not happy with running such high temps as I have a gearbox heater not cooler and I do get problems with high gearbox temps while towing. I do see a drop in coolant temps to 95deg when the gearbox reaches 128 deg, but by then it is too late).

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It’s a 104 deg C thermostat with an electrical heater to open it if needs be.

Well GAP came back with very little, they just asked if the tool is updated to the latest version + didnt appear to want to run through the issue with me unfortunately.

Response..
" If it works, leave it alone. But normally, you can see the engine temp in the engine ECU. "

Yes clearly.

Okay so i worked it out..

I tested continuity back to the ECU and only one wire was working. Referenced the wiring diagram for the sensor. Initially i thought it was the socket, someone in the past yanking on it or something but after sourcing a new connector and cutting the old one, still no continuity on the wire.

Ended up unravelling the wires in the loom and tracing it back. Using the fingernail trick where you drag it along the wire and feel for a break the wire just pulled apart in my hands. Joined her back up, taped everything and its working now. The faulty sensor wire was causing my aux fan to go at 100% all the time so the truck was very noisy. Now i can hear the lifters tapping away lol [bighmmm]

I also installed the Behr TI 32 88 together with a full coolant flush and new BMW coolant. It looks to be working well and keeping temps in check and under 100c

Another thing i noted was that the Transmission Oil temps still went to 110c while the coolant was around 95c.

• Would this indicate the Oil cooler is blocked or the oil thermostat might be a little tired?
• Does someone know the normal operating temp of the ZF5HP24? I can see some people have said around 100-110, but going for a drive up the gorge the other day saw it climb to 120+. Is this normal?