High pitch squeal/humming when car starts first time in the AM

My truck has justs started to make this high pitch squeal/humming when it starts for the first time in the mornsing. It usually does it when the temp in in the teens or lower. I checked the oil levels, coolant. It does not make this noise after the car temp warms up. Also does not do it the rest of the day. I did change to a different oil, 10-30 wt, high mileage.

I have a 528i but just had my car serviced (routine) and the coolant light kept popping up even though I added coolant. One of the questions they asked me was, “was it making a squeal when I started it up.” I’d check with BMW, advice is free. They have something called fastbreak in NY and the service techs will answer anything online.

You need to check the condition and the tension of the belt(s) that drive your alternator, A/C compressor, PS pump, etc. A slipping belt is the most likely cause of this problem in cold weather.

If that does not resolve the problem, then I would suggest that you check the bearings in the belt tensioner and idler pulleys. It is possible that the lubricant in those bearings has dried out.

What year is this truck?
How many miles are on the odometer?

I doubt that BMW will have any free and/or good advice on this Dodge truck.

Tardis

In case you hadn’t noticed, this new poster has posted information specific to his/her BMW in several posts that have nothing whatsoever to do with BMWs.

I was tempted to comment on the same thing that you commented on, but I decided (for once) to hold my tongue–or is it to “hold my keyboard”?
;-))

1997 with 77,000+ miles

Check the belt tension. Squealing on start-up is often a sign of loose or worn drive belts.

77K is NOT high mileage, regardless of what you see on TV. Use the oil specified in the owner’s manual, now and forever. There is no need for “special” oil as a vehicle ages. If there were, the owner’s manual would tell you. But it doesn’t, because there isn’t.

It’s marketing, that’s all.

The oil is not the cause of the noise.

I agree that 77k is not high mileage, and I also agree that the type of oil used in the crankcase has nothing to do with this noise.

However, I am wondering if–perhaps–these are the original belts.
If so, after 13 years, I would just go ahead and change them, rather than waiting for a bad belt to kill the battery and/or leave the OP stranded.

OP–Are these the original belts?