| Author | Message | ||
     Alan Yim (Alan) Senior Member Username: Alan Post Number: 896 Registered: 09-2002 |
Hi folks, I was coming home on the freeway tonight and the noise level of my transmission whine suddenly increased. It was quite a noticeable increase in sound but that was the only thing I noticed. The performance of the truck didn't change, RPM didn't change, just the sound of the transmission whine. It increased in noise level and pitch. I did some searching in the archives and the only thing that sounds similar is the mention of pinion bearings possibly going bad. Does this sound right? This truck just had it's 96,000 km servicing (approximately 1 month ago) so fluids were all changed. Not sure if I should refrain from driving it that much or not. TIA for any suggestions. | ||
| Greg Hirst (Gregh) Senior Member Username: Gregh Post Number: 374 Registered: 10-2002 |
Alan- Do you mean differential whine? Your pinion bearings are in your third members, front and rear. Do you have a lift on vehicle? Did you notice any change when accelerating/decelerating? Check your fluid levels. Do you have a manual or AT? Any fluids leaking? Trans fluid smell burned or discolored? TC, diffs OK? Fluid may or may not be leaking while sitting or may have already leaked out. Look for wet diffs, transmission or TC. Even though fluids were changed recently, a leak may still occur and won't take long to cause damage. | ||
| Alan Yim (Alan) Senior Member Username: Alan Post Number: 897 Registered: 09-2002 |
Hi Greg, It's an AT with no lift. Not really sure if it's differential whine. It's a higher pitched whine that sounds like the normal transimssion whine that I hear. It's coming from the same general area (center to front half of the vehicle), or at least that's how it sounds to me. It happened quite suddenly but nothing about the performance of the vehicle changed. No vibrations, wobbles, clunks or anything like that. Everything appears to be normal except for that increase in whine. If I let go of the throttle, the whine fades away, hit the gas, it comes back but it's defintely a louder whine than what I normally hear and there's no difference in performance when I do that. It happened last night on the way home and was too dark for me to be able to see anything underneath. I'll have a look this morning to see if there are any leaks. The truck does leak a bit of oil but that seems to be normal for it. Oh yea, it's a 98 D1 if that makes any difference. | ||
| Greg Hirst (Gregh) Senior Member Username: Gregh Post Number: 375 Registered: 10-2002 |
It's often hard to pin down where a noise is coming from while driving. If it's actually coming from the area you describe, I would suspect the CDL rather than the transmission as with the LT230 TC you do have some noise but usually not the AT. However, the noise coming and going with accelerating/decelerating is typical for a worn/dry differential. I personally would drain and replace any diff fluids (front, rear, TC/CDL) that I suspected of noise and watch for any crap coming out with drained fluid or low fluid levels. Any seepage from pinion area? Also check your U-joint condition. Have you ever replaced them? Get underneath and check their condition. Any water crossing recently? Any discolored fluids? Are your axle breathers in place and operating correctly? | ||
| Alan Yim (Alan) Senior Member Username: Alan Post Number: 898 Registered: 09-2002 |
Greg, I had a look again this morning and nothing out of the ordinary is visible. No leaks or sign of leaks, no puddles underneath or anything like that although it was about -10*C this morning when I was looking so fluids were probably a little thick. I took it out for a test drive afterwards to test out the CDL and see if anything unusal. Everything worked, Hi and Low in both locked and open positions and it didn't seem clunky. It shifted in like normal. That transmission whine that I normally hear just sounds louder to me and I know it was louder last night for sure as I suddenly heard it over the radio. No water crossings. U-joints are original but I'll have a look at them this afternoon. Thanks for the tips. | ||
| quentin charles neil ross (Qcnr) New Member Username: Qcnr Post Number: 31 Registered: 10-2003 |
If the truck seems to leak a bit of oil (prevoius post) but doesnt now (last post) MAKE SURE there is oil to leak........ Just a suggestion  | ||
| John Davies (200tdi) New Member Username: 200tdi Post Number: 12 Registered: 07-2003 |
I had a similar thing happen, driving on freeway whine suddenly gets louder. The whine was louder than mud tyres and a Tdi diesel. It turned out to be transfer case. Intermediate shaft moved a bit and then the gears started a new wear pattern. Was adjusted but the only thing to fix it was new gears. Get it checked straight away and you may be lucky. John D | ||
| john mac (Mcale) New Member Username: Mcale Post Number: 7 Registered: 07-2003 |
What about your turbo mine has become noisy around 2000rpm, I couldn't work out what was wrong when my truck was running in the workshop noise was gone didn't matter what the revs were i eventually took of the 2 bolts and cover plate on the exhaust manifold and this let me hear the turbo working the turbo whine was the noise had a leak in the manifold gaskets due to a bolt coming loose | ||
| Alan Yim (Alan) Senior Member Username: Alan Post Number: 907 Registered: 09-2002 |
Finally figured out what it was. The viscous coupler for the fan seized. That was the noise I was hearing. Apparently those things make a whack of noise when they seize like that and from inside the cabin, it sounds like transmission/transfer case whine and it only becomes audible when you accelerate. I ended up looking in the wrong place to begin with.  Fixed it today (it only takes 15 minutes to replace) and my truck is back to itself and amazingly quiet when you listen to that racket for 4 days. Thanks again to everyone's input. I appreciate it. | ||
| Greg Hirst (Gregh) Senior Member Username: Gregh Post Number: 376 Registered: 10-2002 |
Good for you Alan- |
