Mitchell Overdrive - noise to expect

[josh1331]

Have Mitchell old in car, letting off on gas I get sort of whirling noise, traveling, I get a little of same. Does anyone experience same ?

[koates]

Hi there, The Mitchell overdrives tend to get rid of their oil a little out of the breather tube. It pays to keep a close check on the oil level fairly often. Regards, Kevin.

[josh1331]

Thank you, overdrive comes with tube you install and you install overflow fuel filter I think on top to take care of expansion then it leaks back down upon cooling.

[Dodge]

The ones I have driven have been very quiet maybe its the rear end?

[flatmotor40]

Mine is quiet and I put a line from the OD to the rearend top bolt for a vent.Tied both to filter up higher that unit

[whizzernick]

Sponsored Links (Register now to hide all advertisements)

gears are straight cut . so except some noise

[mrtexas]

Originally Posted by whizzernick

gears are straight cut . so except some noise

I don't think they are.

[Ol' Ron]

Wet to Bville with JWL back in 02 5000 miles round trip and it never made a sound. I think it's a great unit.

[jake197000]

sounds like rear end noise.

[Planojc]

gears are not straight cut as mrtexas said.

[josh1331]

What I have found out so far is they will overtime quiet down as they wear in , this was from Mitchell. Checked everything ..all ok. It' takes pla CEO as you let up on gas pedal , very little sound and when below 40 mph it sings a very little not loud but you can hear it after 45 you can't hear. Others have said it does have a little whirl sound. Especially at low speed. John

[jagnweiner]

So other than the noise, how do you like it? What car are you using it in? Hoping someday to get one myself.

[rotorwrench]

A rear axle with too much play on the pinion to ring gear mesh can get pretty loud when you have it under load then quiet down completely when you let off the throttle. This is usually due to worn pinion tapered bearings that no longer have the correct pre-load. This allows the pinion to go off center under load. Makes for a loud groaning sound when this happens.

Yours is the opposite since it makes a sound when you let off. The planetary in an overdrive should run pretty quiet. Many of them freewheel when you let off. It might be the overrunning clutch that is making the sound if it has one. I'm not familiar with the innards of a Mitchell.

[josh1331]

Rotor wrench, Rear end is in fine condition, when not in OD there is not a bit of noise. It's definite an OD noise. But also was told it takes about a few thousand miles to break in .

[trevo]

Interesting am finishing off fitting a Mitchell will post an opinion after a road test in a couple of weeks

[Talkwrench]

Let us know how you go Trevo.. How did you get yours in NZ ?

[trevo]

Talkwrench I got mine from Mitchell Manufacturing a year or so ago waited for winter to do the job ended up sidetracked with a brake upgrade on my Boss so have another couple of weeks before it's ready drive I don't work night and day anymore ha ha!

[Talkwrench]

So you just got it regular post?

[Automotive Stud]

Mine is quiet. I run 80w140 gear oil in it though.

[trevo]

Talkwrench no it was picked up from there plant by Mainfreight and shipped down here. I preferred to organise my own freighting took a few weeks to get to NZ