Hi Folks,

Apprecaite any thoughts on this.

My max is making a noise when I make hard turns from stop only under power.

If I make a tight turn not under power, no noise.

The noise almost sounds like a power steering whine (only worse) but I don't think it's that. I almost feel the wheels binding up a bit too, like i can hear the inbound tire breaking loose a bit.

THis all started after I had trans service at the dealer (trans oil change).

This also only happens when the car is hot. Cold this doesn't happen. Makes me wonder if they used the wrong trans oil, does HLSD trans take special oil? Thanks for any help or related experiences.

 

check the axles and wheel bearings. i havent heard of any HLSD failures..

 

I highly doubt its your Hlsd. I agree with hotshot check axles. I also have Hlsd and its not really something that will cause problems....except the smile on your face when your cornering at high speed

 

Thanks for the replies!!

It might even be power steering. Hard to tell. I tried listening to it this morning in my work parking lot but had to stop because I didn't want anyone to think I was crazy driving in circles.

It's louder going left. Seems like the noise is coming from the power steering area (sounded like right front to me.).

I can't imagine how it could be PS though. If I'm full stop and wrap the wheel from lock to lock there's no noise. I only get this noise when in gear, just starting out, hard turn, under power, and the car is hot. If I take my foot off the gas, the noise goes away. It goes away if I hit the gas hard. I also feel the inbound tire getting power which pushes the car into understeer.

That's what makes me think it's the LSD. I've read in other fourms of folks complaining about a "whine" with HLSDs. It would make some sense in a tight turn, with the bias and all...

Could be bearing of CV joint too. Are those covered by the 5/50 drive train warranty?

I'm gonna drop in on the dealer sometime this week. I'll post back whatever it is, I'm stumped.

 

Hi Folks.

Just got back from the dealer where I had the original MT service done.

Tech drove with me and he seemed surprised by the noise.

They checked my records and they used a synthetic 75w 85 trans oil.

They decided to try factory fluid and that fixed the noise and bias issues.

Soooo, it was the HLSD making the noise. SInce this was only happening when the car was driven for a long time, I suspected fluid and was right.

I've used synth MT fluid in my other car, and I've noticed it thins out faster than regular oils and has shoter life. This all has me wondering whether synthetics are bad for MTs. This is the 2nd time I've seen sythetic trans oil wear fast and make for a noisey trans. In my other car, the bearings start to whine when the oil gives out. It gives out much faster than regular oils.

The dealer has been very good about it. I can't really fault them for trying a synthetic, the Manual calls for 75w 85 or 90. That's what they used.

The rest of the trans sounded fine, the HLSD just did not like the synthetic when it got hot and thinner. The noise was aweful.

I'd love to know why...

It's fixed, sounds and runs like new. Plenty of warranty left and the issue is documented.

 

synthetic is fine, lots of people on here use the redline mt90 which is synthetic and they love it. congrats on getting the whine fixed though

 

I've experienced this condition as well, but on my mustang using an Auburn cone type differential and using the Redline gear oil. This is my theory: Once the fluid comes up to temp, the synthetic thins out more than conventional fluid. Because the diff isn't submersed in the oil and gets is lubrication from the ring gear flinging oil around the housing thus allowing the fluid to drip from the top down into the diff, it looses it's "oil cushion" and starts making metal to metal contact and binding during the defferential action. It doesn't help that centrifical forces are at work pulling the thinned oil out of the diff while moving. Once I put conventional Valvoline diff fluid back in, all quiet! Again, this is just my theory.

 

Thanks for the feedback, I was beginning to wonder if it was just me.

I've read on some unrelated sites that synthetics, even if they are in spec for the grade, aren't good for limited slip diffs. I think what I was hearing and feeling were the dry clutches in the diff binding up. Somehow, when the Bias is high, they send too much torgue to the slower wheel. Kinda like the old LSDs on muscle cars when we used to stretch the springs to make them tighter and you'd hear the planet gears skip when you went around a tight turn.

I don't understand LSDs enough to even venture a guess why.

I've been driving the a lot since they put dino back in and it's been fine. I'm a bit worried about any wear and tear it might have caused but I just don't notice anything.

 

as long as you put the right weight in its the same oil, just better.