Can Sub-Zero Temps Effect the Drive train?

[BAYOU]

So I've had my TE for about 6 months, and it is amazing. Lately we have had sub-zero temperatures and I am feeling and hearing a rhythmic thump that seems to be coming from the front end. The first time this happened I figured there was snow or ice inside of a rim or on an axle, or a rock in a tire tread. but after crawling around under the truck for as long as I could stand the cold I could not see anything. The weather warmed up and the thump was gone.

Yesterday the temps dropped again and the Thump was back. I have checked all the treads, and rims, and I don't think it can be a tire balance issue since when the temps warm up it goes away.

Could it be that the tire pressure is dropping at -8 degrees to a point that I am feeling the really sub-standard tire that came on the truck?

Thanks for any input you may have.

 

[NHinAK]

I just had my Transfer case replaced because of a rotational "thump" that would come and go. However, it was most prominant in the cold weather. I've had my truck down to -40, and it was pretty loud.

Check out this thread, and my posts in it to see what, and when it would happen.

http://www.toyota-4runner.org/5th-gen-t4rs/98965-strange-noise-rear-end.html

 

[BAYOU]

Thanks for the reply, I have only noticed it at 0 F to -9 F, I read the thread you sent and I will try and switch out of 2hi to 4hi and see if that corrects the issue, but all the other symptoms are consistent with yours. when the weather warms up I haven't noticed it though.

 

[Rob_G]

I just had my Transfer case replaced because of a rotational "thump" that would come and go. However, it was most prominant in the cold weather. I've had my truck down to -40, and it was pretty loud.

Check out this thread, and my posts in it to see what, and when it would happen.

http://www.toyota-4runner.org/5th-gen-t4rs/98965-strange-noise-rear-end.html

You got yours finally fixed? I'm still living with the thump because my dealership can't reproduce the problem. Yet the shop foreman heard the noise, but he thought it was tires. It hasn't been bad lately, but colder weather sometimes makes it worse. There's also a slight thump when shifting 4HI back to 2HI which I don't think should be there, but the same shop foreman says is normal.

ugh!

Rob

 

[Jtraskell]

You got yours finally fixed? I'm still living with the thump because my dealership can't reproduce the problem. Yet the shop foreman heard the noise, but he thought it was tires. It hasn't been bad lately, but colder weather sometimes makes it worse. There's also a slight thump when shifting 4HI back to 2HI which I don't think should be there, but the same shop foreman says is normal.

ugh!

Rob

Rob, print this thread and also especially the thread referenced above. MAKE the SERVICE MANAGER read it. Then see what happens......

 

[1engineer]

First, cold weather can play havoc on a drivetrain, from the engine to the rear end. Synthetic lubricants can and will in most cases solve the viscosity delta issues (sub zero temps) associated with petroleum based lubricants. This includes gear oil too. Automatic transmissions and brakes usually do not have much problems with cold weather because they have additives to maintain a proper viscosity throughout a wider temperature delta.

My advice would be to change out your diff lube with a synthetic for below zero applications. It will still be fine for high temp just won't change viscosity much in low temps. All the equipment we design to go to below zero climates (Antarctica, Noth Alaska, North Sea) will always have different lubricants than "normal" climates. Why not put these in as standard? Simple. It is way more expensive to put special hydraulic fluids and gear oils when normal lubricants will work in more temperate zones. There are conversion charts that will help you select the proper synthetic diff lube.

I know I have not fully answered your question on the noise but I suspect it is caused by a lubricant that is too viscous. A simple test is to take some of that lubricant in a bottle and put some of it outside in sub zero temps and inside at room temperature.

 

[BAYOU]

THanks for that, I have heard that royal purple and Amsoil are good synthetics. I spoke with my dealer yesterday and of course they could not hear the noise as it was only 22 F or -4 C (a real warm front So if I am understanding correctly it can't hurt to put in the synthetic correct? even when the summer temperature swings the other way to 90 + F?

 

[1engineer]

THanks for that, I have heard that royal purple and Amsoil are good synthetics. I spoke with my dealer yesterday and of course they could not hear the noise as it was only 22 F or -4 C (a real warm front So if I am understanding correctly it can't hurt to put in the synthetic correct? even when the summer temperature swings the other way to 90 + F?

Synthetics, like Mobil 1, generally operate better at high or low temps. Talk to your dealer and get a list so you won't void warranty. Let me see if I can explain it simply:

Synthetics, like petroleum based lubricants, offer the same "Lubricity" (fancy word for how slick it is) at nominal operating temperatures. The big difference is synthetics have less of a change in viscosity (thicker when cold, thinner when hot) than petroleum lubricants. This rate of change is the viscosity "index". I have witnessed gear oil solidified in sub zero conditions.

 

[BAYOU]

Great thank you again, and I will check w/ the dealer so as not to void the warranty. Are there other fluids that I should change out while I am at it? I have always run Full Synthetic Motor oil, but have to be honest I have never thought of the other fluids. This is my firs T4R, though I have had 4 Tacomas before it, and I never had this issue with them.

 

[JB.]

Yesterday the temps dropped again and the Thump was back.

Does it go away with some driving?

Could be as simple as a little flat spotting in the cold tires. It would take longer to go away in the really cold temps.

 

[BAYOU]

It did not go away with approx. 25 miles of driving but I did not have any more time to drive further. I would not be surprised if that could be a part of the problem, as the OEM tires are pretty useless. 1engineer suggested the synthetic gear oil so I think i'll do that as it can't hurt and will benefit the truck in the long run. Thanks for the input-