J.Berta

Have a 95 Integra still with b-series engine/trans. Bought a complete rebuild kit and a 4.7 final drive from a company. Not only did I use all the supplied bearing from their kit, I also changed the carriage needle beaarings between both shafts and gears. So every bearing has been changed along with diff bearings. I'm using a oem ITR diff with B16 2nd and 3rd gear, gsr 4th gear, and LS 5th gear. Everything works great but the final drive is whining. And its not getting better or worse. Has anyone had any issues with their helical final drives having whining??? The company final drive I have is made by Gear-X.

seelback

I've heard about aftermarket final drives whining, they don't get better or worse, just stays the same. My buddy has a mfactory 4.9fd in his d16 ex tranny and it whines and doesn't change. Some people are saying it's the cut of fd. I would call gearx to make sure this is ok.

yungmulacrx

I have the whine from a mfactory final drive..

J.Berta

I have contacted the company that I purchased the equipment from. They are/seem to be concern about the situation. And they have contacted GearX about this. Said GearX is requesting the parts before doing anything. And may or may not do anything about this. When I contacted the supplier of this fd, the contact said the helical cut wasnt prone to whine, and he hadnt heard of one whining. Which a straight cut is a no brainer, is nothing but whine. I have friends that runs MFactory and etc fd and theirs doesn't make a whine. Just wanted to check in here to expand on what others are experiencing with their fd's.

Thanks for you guys input!

J.Berta

I assume yours is a helical cut??

MFactory

OEM final drives are full helical. These provide almost noise-free operation, but also are the least efficient (i.e most parasitic drivetrain loss)

Straight Cut final drives are the reverse. These are the loudest in operation, but are the most efficient (i.e least parasitic drivetrain loss)

All of our final drives are semi-helical cut, which is kind of a compromise between the above two (i.e less operational noise, less parasitic drivetrain loss). Is there a whine? Yes, more than oem, but less than straight cut.

AFAIK, the Gear-X 4.785 final drive is also semi-helical cut, so yes, it should have an audible whine to it and is nothing to be alarmed about (unless it is seriously loud of course, of which then usually indicates another problem(s))

In terms of "whine", a lot of this actually depends on the driver believe it or not. What is "noisy" to some, might not be noisy at all (or possibly even inaudible) to others. This is, of course, on top of general car noise, type of fluid in your transmission etc

J.Berta

Thanks!!!. The whine is very much liveable! I only called them to ask if theirs was noted to make a whine, in which the guy said no and had no explanation. So that threw a flag. The supplier has been calling and doing his best at their customer service. Very polite and professional.
But as you explain, it makes since. I can definitely live with the whine. Just wanted clarification. And yes some ppl are more **** than others. Lol Some ppl believe there is a perfect world. I was going to call you guy to refer to your line of final drives.
But thank you for your input/info! Geatly appreciated and look for future business with you!

yungmulacrx

Yes mine is helical.. I was concerned at first but was assured a slight whine was normal.. I have put several miles on it and the noise is still the same since day one.. Fwiw im running torco mtf..

J.Berta

I'm running Honda mtf.

94civiccupew/b7

I had a gear-x 4.9 FD in a y8 tranny and it whined a bit also but never had any problems. you will be just fine. and Mfactory thanks for the explanation

Runnerdown

Whining sounds can also be amplified by engine mounts. Oem type mounts will not transfer as much through the chassis, a rigid urethane aftermarket one would be louder.

HYREV2NR

This is the first I've ever heard of such "gear whine" from an aftermarket F/D for a Honda. I know all too well that straight cut gears are stronger because of my experience with old RWD domestics and M-22 "rock crusher" gear boxes.

Being an ITR owner noise is never really an issue with me unless it's the sound of a fart-can exhaust at HWY speeds.

So my question is,...how bad is the whine and does it increase in volume the more you accelerate? Note that I do have semi stiff motor mounts. Thanks MFac for bringing this to my attention.

Aquafina

iTrader: (3)

It isn't bad. I did a 1,600 mile round trip with the MFactory 4.05 FD (semi helical) and MFactory 1.028 5th (straight cut). Maintained 80mph most of the way (5k RPM) and it was very tolerable. With the windows down I could still hear the CD player no problem (rear speakers only too). Noise increases with RPM and is manipulated by throttle input. When cruising it barely takes any throttle to maintain speed and the gears are pretty quiet. Roll into the throttle and they will get louder.

J.Berta

My fd whine isn't bad either. Very liveable. You hear the whine under acceleration, and it is at a higher pitch. Then hear it under deceleration, and its at a lower pitch which the gear is hitting the opposing side of the teeth.

HYREV2NR

Thanks man. That would never bother me in an ITR especialy since it's not a DD. I've been looking seriously into the gear theory instead of crazy engine building.

J.Berta

No problem. My car is my DD tho. So I get to hear it the whole trip. I would have cared less about if the gear had whined in the beginning if it was a track car. lol But the 4.7 fd is quite nice even tho its my DD. I commute 30 miles one way. Have B16 2nd and 3rd, gsr 4th and LS 5th gear. With the LS 5th, my "rpm vs speed" is the same as a stock gsr trans in its 5th gear @ 80mph.

HYREV2NR

I figure the whine might just add a nice touch to the symphony of all the other sounds of the car, kinda give charater ya know. Then again, I could just get some cheese to go with that whine.

94civiccupew/b7

lol this guy

hotbricks

Good Point, of course.
Soft Std. mounts obsorb vibration/noise and reduce the transmission of same.
At the other end of the scale. Solid mounts transmit all feel, vibration and Noise