I have noticed after driving for a few minutes, if I am decellerating (as in, if I'm driving from 25-30mph and decellerating to 10 or so mph) I hear a howl. A mechanic buddy of mine said while we were driving that it is possible it is the transmission since it is beefed up, it might have something to do with the shift kit perhaps? I'm not sure about any of it. Any thoughts?

It could be your ring and pinion when was the last time you changed the fluid
I change mine every spring

the rear end was actually just rebuilt. They are 3.73 GM gears.

I have Richmond 3.73s and they Howell when ever im off the gas
the gears are cut a little straiter which will make the gears howl
Also when the Tranny was built a straiter gear set could have been installed which would make it howl also
The straiter the gears the stronger it is

oh ok so potentially if it is a strong trans, it could howl? is there a way to tell what it is from?

I wouldn't be to concerned about it sounds like a built Tranny and axle to me

pre-load in the rear may not be enough. Grab a torque wrench, drop the driveshaft and check it. Too loose and they howl ( no dirty jokes guys )

The Richmond Gears are cut for racing and were not ment for a street drivern car. Learn to live with the howling or change the gear set to something besides Richmond.

I have GM gears.

Then the rear gears wernt set up right, or an axle bearing is going bad.

i like the built trans reason better, lol

Who wouldn't lol? I would have preferred my timing possibly being off to be the cause of my loss of power and stuttering instead of my fuel pump, but that wasn't the case.

no tranny will make sounds when done right...lol.
whos telling you this billy bobs tranny shack...lol

richmond gears will not make any sounds. unless set up wrong...lol

have used just about all makes of gears. this how i know.
3.42s 3.73s 3.90s 4.10/4.11s 4.56 4.89s have run them all
you name the make...


sounds like radio feed back when you let up on the gas= set up wrong

apparently the howling only happens when I let off the gas, so I think that's indicative of the trans.

Sounds like the coast side of the gears is the problem then.

must be a stick shift then.

once off the gas there is no load on an auto, unless your manualy downshifting it to soon.

it is actually an auto

The 700R4 shouldn't howl, even if it is modified. The only "gears" in the unit are the planetaries which are helical(meaning cut on an angle). The upgrade to the OE 3 or 4 pinion stamped steel or aluminum punks are 5 or 6 pinion welded steel case planets with hardened gears. The upgrades are still helical and don't make noise. The auto should have a decel detent or coast clutch, unless it was deleted as they sometimes are for race only applications(I hate this mod). But short of a damaged planet or case the 700R4 should not be noisy. I agree with those who say to check your rear diff gear alignment. I use basic anti seize as gear marking paint after allowing the gear lube to completely drain. Roll the gears forward then rearward and look for the contact pattern on both sides to be as close to the center of the tooth as possible. Also, what weight of lube are you running? On any performance application I recommend atleast 75-140 synthetic.

i am not sure about the weight ... i'm gonna have someone check it out. the guy that was over here just listened again and he said he thinks it def. isn't the rear which is odd.

I hate to say this, but who did your trans? Has it made this noise since it was done? Is it possible that a trust bearing was left out? That could cause a noise I suppose. I know that my extreme TPI went though three trans builds before my boys at Oregon Trans built the one that's in it now. Is your trans fluid still bright red? You know what fresh clean trans fluid smells like right? A little like fresh fish. Does yours still smell fresh or does it have a burned fish smell.

The transmission was built about 7 years ago - it probably only has 2k miles on it since then, and only 1/2 a mile on it for the past 7 years or so. The trans fluid was drained and just put in again for the first time about a month ago. I havent taken it over 35mph or so yet, but it shifts firm, so i'm not sure.

I don't think its your transmission either. Think of it this way, when your accelerating or cruising the load is on the drive side of the ring gear, but when you coast the the pinion stops pressing on the ring, and the roles are reversed. So during coasting your pinion is in contact with the coast side of the ring gear. I think this what a lot of others believe to be your problem as well.

+1