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Discussion Starter · #1 ·
I've Got a whine between 60mph and 70mph only when using the gas in my 85 No LSD.

Now I've also got an 82(non lsd) I was think about swaping the rear.....They should match up right???
 

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Chaning the rear

The rear end will physically bolt in. They are identical externally. Now, you need to know what ratio differential you have in your two cars. If they are the same ratio, then the speedo will read the same. If the ratio is different, then you will have to replace the driven gear in the side of the transmission that feeds the speedometer, or your speedo will read wrong
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Welcome to my world: I have tired of trying to find used speedo gears from list members and am trying to track down the right dealer part numbers for the 3.73, 3.9, 4.1, and 4.3 speedo gears. See my post on part number from Jeff Watson earlier today.

To find out the ratios, if your car is still stock, refer here to check the build plate under the hood on the firewall:
http://www.celicasupra.com/othercodes2.htm
 

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Discussion Starter · #3 ·
Ok, litte booze on the breath(its late), but I'm going to the shop early tomorrow, so before I spend the time to pull the rear should i also pull the speedo to elimimate the difference between the years???? Ratio ect. ???

And yes I'm all stock.
I'll check your link tomorrow.
 

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Speedo gear summary

I don't know if you had the chance to scan my thread about part numbers from Jeff Watson, but here is the lowdown:
If your car already has a 3.727, 3.90, or 4.10 rear end AND you are swapping to a 3.727, 3.90, or 4.10 rear end, all you have to swap is the plastic gear on the end of your speedo cable in the side of the tranny. You don't have to change the metal drive gear inside the tranny.

If you have a 4.30 rear AND are going to a 4.30 rear, then the same holds true: you just have to change the driven gear in the side of the tranny.

If you are going FROM a 3.727, 3.90, or 4.10 rear TO a 4.30 (or the other way around), then it gets complicated. Both the drive gear and driven gear have to change.

Because....
3.727 is paired with a 31-tooth driven gear and a 11-tooth drive gear
3.90 is paired with a 32-tooth driven gear and a 11-tooth drive gear
4.10 is paired with a 33-tooth driven gear and a 11-tooth drive gear

4.30 is paired with a 35-tooth driven gear and a 10-tooth drive gear

And here are the part numbers I have been able to dig up
31-tooth = 33403-29145 = 3.727?
32-tooth = ??
33-tooth = 33403-29115 = 4.10?
34-tooth = 33403-39075 (what this is for I don't know)
35-tooth = 33403-19235 = 4.30?

If you pull the driven gear, it should have a number printed on it that is the tooth count (or you could count the teeth).

I have heard that if you have a flashlight, you can look up the output shaft (with the driveshaft out) and read the numbers on the drive gear.

Please let me know what you find, as I am anxious to find out if the info I have dug up is accurate.
Thanks
Brian
 

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Big Dumb Correction to my last post

>If you have a 4.30 rear AND are going to a 4.30 rear, then the same holds >true: you just have to change the driven gear in the side of the tranny.

Ignore that!

If you are going from a 4.30 to a 4.30, then nothing needs to change. That's what I get for typing in the morning with no caffeine!
 

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Discussion Starter · #6 ·
Well I was all set to pull the drive system out of the 82 when HEY!!!!! its snow/ice/raining, so give me a few days and I'll let you guys know.
 

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Called the dealership

I did some part number checking, and I am a bit unsure of what he told me means:
I have the 4 part numbers
33403-29145
33403-29115 = 3.727? = 33-tooth
33403-39075 = 4.10? = 34-tooth
33403-19235 = 4.30? = 35-tooth

He says that for my '83 Ltype (no Performance Pack) takes the 33403-29115 (33-tooth), which means that the 33-tooth is paired with the 3.727 rear.

He says that for the 83 with Performance Pack, I would need the 33403-39075 (34-tooth). I don't know what differential that year Ptype had. Anyone know? Was it the 4.10?

So where does the Non-USA standard equipment 3.90 fit into the picture, and what was the 31-tooth gear paired with?

Incidentally, all of the above part numbers are $24.89 at the dealer in Florida.
Brian
 

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I have recently put the diff from an 85 Celica GTS info my '84 P-type and have the part number from the dealer for the speedo gear.

32-tooth driven gear part# is 33403-29125
 

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i always thought that the front tires gave the speed to the speedometer

cuz when ever i peel out the speedo doesnt increase in speed, and also when i peel out in water. however i have noticed that when my front tires lock up my speedo goes down to zero.
 

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front driven speedo? Nah, I doubt it. The speedo cable is plugged into the tranny, so for it to read from the front tires, it would have to be awd or fwd. As for your speedo not showing burnouts, I'd say either you have a slipping clutch or your speedo is screwed up somehow.
 

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nope no sliping clutch,
 
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