Ok, i still have no clue what my rear gear is. My tranny has 175,000 miles on it with no rebuild. If i give it more than half throttle off the line there is a loud bang (tranny) and then it starts moving. I'm going to change the fluid and filter soon since the old fluid has at least 5,000 miles on it. According to the calculator on this board, with my 15 in tires, and cruising at 41 mph is exactly 1,000 rpms, my rear gear is something like 2.22 I'm pretty sure that there is no such thing. So, is my tach or speedo off? Do i have the worst rear ever? Does my tranny suck? Is it annoying me? YES. What should i do? A rebuild is in the near future, and a gear swap, but what the hell is wrong? Sorry about the lenght and venting. I'm just mad at this car. Thanks.

~Matt

 

you probly have a 2.73, if its a nine bolt

 

pull the cover and look you don't have to work for nasa to figure out your gear ratio. change your trans mount too while you're under the car.

 

yeah what ede said,

if the rear is factory original, and never been touched. according to this sites, tech data it is 2.73 for an automatic. but still, pull the cover and check, maybe you will find out why your posi is broken while your in there

 

i'm just really lazy. as for the tranny? i find it odd that 41mph is 1000rpms in 4th gear. And yes, it does shift into OD that early. It's a pain. When it shifts i lose power and have to give it more gas or i actuallty slow down! What is the best way to rebuild a 700-R4? I know to use the transgo shiftkit, but what other parts? Corvette servo's sound popular.

~Matt

 

if you're too lazy to pull the rear cover or r&r the trans mount why ask about rebuilding the 700r4?

 

LAZY!!!! .....I believe lazy and thirdgens are an impossible mix .... I ran from my computer desk out into pouring rain and onto muddy ground to look underneath the rear of my T/A . ...Now, lets get with the program !!!!! :sillylol:

 

hey richrad were u afraid there was a dog under your car or something what were ya checkin on

 

ARE YOU SERIOUS! ......rear codes for ratio

 

well jeez u made it sound like it was an emergency

oh i ran from my computer outside in the pourin rain and got down on the muddy ground underneath my ta

i thought there was a possible problem that u thought was happenin but i guess i was WRONG. sorry but i am not stupid like u are thinkin i am. its just your wording that got me

 

it's not so much that i'm really lazy, but that i'm in philly and my car is in NJ. Does anyone have the codes for the rear gear ratios? Thanks. Winter, spring and summer breaks are my only chances to work on my car. Until then i'm trying to figure out what is wrong and what i need done soonest. Just doing a little research.

~Matt

 

I just found mine ... here ya go:

http://www.iroczone.com

Under Technical, click Specifications, select year and Rear Axle in drop down boxes, and codes are listed. Tells where codes are at bottom of spec screen. Codes are impossible to see, use WD40 or carb cleaner and steel wool to fight the grime ... codes on front of pass side axle left of diff (about 3 inches left) ... 1st three codes will match something in this list.

If your ride has passed through many owners, then might need to pull cover off rear as suggested bu others. If you know it's past owners and are relatively sure no alterations have been done, chances are you have what the axle code specifies.

Laziest way (and least guarantee) is RPO codes, located in console. Check VIN on RPO code sheet to make sure it matches (I have a parts car with a different console installed, thus RPO codes were wrong.

 

Oops! Forgot to mention ... as someone said above, replace tranny mount - that might be the loud noise. My Camaro RS did the same thing - was a $20 part and 15 minutes work!

I also did motor mounts - another $30, and 45 minutes work!

(sorry, I had access to free lift usage - may take more time and larger cuss-word vocabular on the ground)