Overdrive questions

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83kid

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Hi,
So i recently bought an 83 k10
Not sure on what transfer case or transmission is on there, its automatic, but when i bought it the guy told me to drive around town or most places to put it in 3rd, and when i got to around 60 or so on the highway push it up one, and that puts it in overdrive. Works great and everything, needle isn't right though.
But i was wondering: Why would this be? Not sure if it came with an overdrive or the guy put one in it or something.
When i go to shift from park i go down to 3rd, but i can just put it in D and the needle is fine. Haven't tried driving it in D yet besides on the highway. But when im going, and then shift up one place the needle moves somewhere in between R and N, and then when im going shifting up from 3rd, without having gone into overdrive, the needle is way off, say if i was driving and havent put t in overdrive since i started driving around, and i go to put it in reverse, the needle is almost near P.

I don;t think it can just be the needle is out of adjustment or whatever because it is good putting it into gear.
Pretty much i'm just wondering why this all is. What is the advantage of driving in 3rd over D, and why would the needle be off?

Thanks!
 

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What size tires on it? I'm just speculating here, but it sounds to me like what someone would do with upsized tires on a numerically lower axle ratio like 3.08s. That way the thing won't creep into OD when you're doing 45 around town and constantly strain on the tranny.
 

MrMarty51

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So, the indicator only has a "D" and not a sort of a square around the "D" ???
I would be for crawling under the vehicle and see exactly what transmission it does have.
It is possible that someone has installed a 700R4 transmission into an older boday that does`nt have the O.D indicator to the shifter.
The cure, if it in fact does have a 700R4 would be to find a vehicle at the scrappers that has the O.D. indicator and grab onto it, install the O.D. indicator into Your dash and all`ll be gooood.
 

Boone83K10

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I agree, it has a 3 spd indicator and actually has a 4 spd installed.
 

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It doesn't hurt anyhting to drive it in town in 3rd and when on the highway put it in OD. That is how I drive any vehicle that has an OD even if it's a manual transmission, except if it's a manual it is in 4th not 3rd. There is no need for OD in town.
 
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Boone

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Mine has 35s and 308 ratio so thats how i drive it too. Already put a new trans in it (no fun). So no overdrive for me unless im on interstate. Need to upgrade my ratio soon.

Sent from my SCH-S720C using Tapatalk 2
 

83kid

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Well, i dont think it has a 700r4, in hotrod's thread for identifying one, i dont have the numbers on the back passenger side of the transmission that should be there, no numbers there at all.
No clue what kind of transmission entirely.
Other than the number thing, it looks quite similar to the 700r4 (atleast on the passenger side)

For tires its got 33's, and the guy said a previous owner had put a lower axle ratio into it, he didn't know what ratio though.

And, the indicator goes:
P R N D 3 2 1

D i dont believe has a box around it, don't remember one and i'm almost certain it doesn't.
Above it, it says automatic overdrive, but it is not an automatic overdrive.

Any clues as to how i will know what transmission i do have and all?
 

DoubleDingo

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Post some pics, that will help.
 

83kid

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Sadly haven't had a chance to take any pictures and upload them. Going to be doing a few things to the truck tomorrow so i'll probably take some then.
If this helps at all, i am pretty certain its a 3 speed. Sounds like it, at least up to around 50 it does.
So, is there any transmissions that have an overdrive and are a 3 speed that are in these trucks, or would it be a different transmission that someone installed an overdrive into?
Quite new to vehicle drive trains and such, learning more and more as time goes on though.
 

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th350c Its a legit 3 speed with converter lockup, which is why alot of people say its like having another gear, it locks the converter 1:1 instead of slipping, no matter what- a converter is ALWAYS gonna have some slip, unless its a lockup its never truly 1:1.
 

83kid

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So after so long i finally started looking hard to figure out what the transmission is... and to the best of my knowledge it is a 700r4, just to wrap up the thread, thankds for all the help everyone though!
 

Boone83K10

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Are you getting overdrive with lockup? Don't want to burn up that trans..
 

83kid

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Whats the difference/whats the lockup do?

I have used overdrive twice, and neither times for long, it only gets to about 3000 going 70 without even being in overdrive (I wasnt driving like this, i was only going like 60ish, just wanted to see)
 

Boone83K10

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Lockup feels like another gear. It allows the engine to ruin at lower rpm at cruising speed. Easiest way to test its to get up around 60. Lightly puts the brake pedal, does it feel like a downshift (do engine rpms go up)? Let off and see if it "locks up". If you dont feel a change then the trans isn't locking and can run hotter and burn up.
 

83kid

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Alright ill try that soon, thanks! Doing this in overdrive, correct?
 

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