senicalj4579

iTrader: (41)

Had my 3.73 installed along with the new setup. After I got the car the gears did make a little tiny noise on decel at 55mph but nothing bad. Been driving the car for 4k miles and its been fine.
BUT, a few nights ago at the track the car did a couple low 11 second passes. Now the gears are whining at low speeds and even higher speeds than before. Some of the sounds at low speed are pretty funky. How much longer would you say this thing will live? lol

01ssreda4

iTrader: (96)

What kind of gears? Did the rear get a complete bearing refresh?

85CamaroZ28

iTrader: (7)

My Motives do it now too. After about a year of hard driving they whine pretty bad. Especially on decel at highway speeds. Mine got a complete bearing rebuild too. They were set up a little tight but I have had them in for 30k miles now and yeah they whine but the rear is still holding up. IDK for how long though.

ULTIMATEORANGESS

iTrader: (4)

these rears really dont like abuse. its a gamble every time you sink money into them.


its probably best you have them looked at ASAP before a complete implosion occurs.

senicalj4579

iTrader: (41)

Well they are motive but I read theres 2 different kinds? IDK with one they are. The #s descibing the gears are mgr-g875373. They were installed with a new 7.5 install kit but thats all I know.
I changed the fluid after around 1k miles or so. Fluid looked good. Old oil was valvoline 80w-90 and new fluid I put in was lucas 85w-140.



OK good, thanks for the info. Maybe it will last me a while.


Maybe....

01ssreda4

iTrader: (96)

You got the orange box Motives. I had the same in my 10 bolt. Loudest set of gears Ive ever been responsible for installing. Blue box Motives are typically dead stock silent.

senicalj4579

iTrader: (41)

Alright thanks. I tried looking on summit racing and search but couldnt figure out what color was which. Does this mean the orange is not as strong as the blue?

redbird555

iTrader: (14)

No quite the opposite the orange motives are made of a tougher alloy which consequently makes the more prone to noise. These maybe noisy but then again you may have broken the blue ones if you had them lol. I want to do 3.90's in my rear but they only come in the orange box so I'm a little skeptical of them being noisy

senicalj4579

iTrader: (41)

Thanks. They can make all the noise they want if they are really stronger and hold up.

2000RATA

Agreed the orange boxed ones are the loudest pieces of dog crap I have ever heard. No other gear I have used has been anything like these. I will NEVER install another set of motive gears. EVER!

01ssreda4

iTrader: (96)

I put some in my 12 bolt and they are a little loud too. I won't be buying the orange boxes again.

My6speedZ

iTrader: (18)

You going to crack it open Joe? Mine has gotten to where it really whines, might be time to go nine inch or your an auto so if you got a good deal on a 12-bolt do that too. I'm doing my nine inch by piecing it together piece by piece to do it on the cheap.

Anthony Williams

iTrader: (3)

Try a different lube(Go back to the lighter 85/90w),3.73 Yukons with Red line shock proof gear lube very little wine, Lucas tends to foam at high stress-rpm..

senicalj4579

iTrader: (41)

IDK ha I just might let it go. I dont think I should waste any time stressing it. I will just have a new rear in mind when it goes.


I ws thinking of going back to lighter fluid. The shop used valvoline 80w90 when they did the 3.73.

My6speedZ

iTrader: (18)

Yeah I hear that, after mine started to whine I decided I wasn't even going to bother trying to make it quite and re-build it or anything like that.

Haha the list of things we want/need never ends smh.

reeperz28

iTrader: (1)

Sorry to bring this one back up how can i tell im getting the blue box motive gears? Where can i order some for a 2 series carrier?

ULTIMATEORANGESS

iTrader: (4)

check with some sponsors.

VincesSS

iTrader: (1)

I'll add to this for anyone who may search in the future.

I just had motive performance 4.10s put in with a solid pinion spacer and a mac girdle was already installed. Even with that 3 1/8th mile passes and a best 60' of 1.9 they are whinning again, but were nearly silent before the track.

01ssreda4

iTrader: (96)

Blue box = Part number starts with GMxxxxx etc
Orange box = Part number starts with G8xxxxxx etc.

Typically GM or G8 then rear size then gear ratio. So a 373 for our car in blue box would be GM75373 (7.5 being the size of the ring gear). If you want a 2 series add an X to the end for a thick cut gear.

So a blue box 373 in a 2 series would be GM75373x

wrd1972

iTrader: (12)

OP, same thing happened to me with my 9". Gears silent for 2K miles, go to the track, make 4 passes and they scream bloody murder on decel on the way home. Gears were ultimately destroyed.

I blamed it on the 80/90 RP synthetic gear oil I ran and found other instances on the web were others believed this burned them too. I also blame back to back runs down the track which likely heat the gears up more than anything else on the car.

I had orange Motive gears too. I think you were also running too thick oil for race conditions.

Did you run synthetic gear oil?
Did you make back to back runs?