What is the difference between the overdrive and the ordinary drive on an automatic V8 305 bird? Is one easier one gas? Does one have more power?

 

The D with the circle is Overdrive gear (4th gear) and is easier on gas mileage.

 

so does the oridinary D have more torque a.k.a more power?

 

well its just a lower gear, just like 1st gear is lower than second gear thats all. overdrive is great for just crusing around and highway use because a higher gear lowers the rpms the motor spins at and therfore saves gas and allows fo a higher top speed.

so if you stick your car in drive it will act liek a 3 speed trans, and top out sooner.

if you use overdrive it will act the same as drive but have one extra gear.

 

You really need to sit down with your dad and have a frank discussion about cars. Not trying to be rude necessarily, but you should know this when you get your drivers license at age 16.

 

or if you want to be like the foxbody rustang guys just stick it in 2 and hammer down... but loads of torque

 

Thats what I figured, I just didn't know if it was different from Dodge, I am a Dodge man myself until I found my thirdgen.

 

hey leave him alone he's from canada.



Better yet do what I do, Manual shift that tranny. Sure you'll kill it faster but hey you gotta have an excuse to get a new one.

 

the guy who wrote that quote is from Calgary, which when last time I looked was also in Canada. lol, but ya I was just curious to see if it was different from Dodge... apparently not.

 

Sonix has a point, understand how the gears of a transmission work. Overdrive is an extra gear, and does not affect the acceleration of the first three.

 

ok my mistake you're all crazy

 

Manual shifting doesnt hurt it one bit...

That is unless your holding gears till 8k RPM

 

if you dont go into overdrive, your torque converter wont lockup and you will have crappy gas mileage. thers a bunch of other factors that are taken into account when the converter is locked up, but no OD is the #1 on the list.

and its no fun shifting manually on an automatic anyways because the auto tranny shifting is governed by oil pressure and throddle position. get a manual valve body, then get some F1 style paddle shifting and have at er'

 

Now were talking!

 

A stock 700R4 will upshift at redline regardless of what position the manual shaft is in.
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The ECM will still lock the TCC normally with the selector in Drive.

The only major difference between the D and O/D positions (apart from preventing shifting into 4th) is that the overrun clutch will provide engine braking in all gears in D instead of allowing coasting in O/D.

 

So you are saying that if you keep it stuck in 1st gear, it will shift to 2nd regardless? I've definitely gotten up there in 1st gear before and this has never happened to me.

 

mine shifts at 5300 rpm, well used to till my moter blow up last night... man i feel sick

 

Yes, unless you have a shift kit which eliminates this feature.

 

..and it will also downshift out of OD at >1/4 pedal, limiting your top speed to whatever you can do in 3rd gear.


Edit: Apeiron, you're a mod now? Wow, congrats!

 

Ah, si senor. At times, I forget that I installed that TransGo kit...its just part of the car now, you dont even think about it

 

ok just out of curiousity in new foundland do you know what the story is behind the city named *****?

how in the hell did they get a name like that?

though still not as good is intercourse, PA you have to drive by blue ball to get there though. sad thing is they are both true names for cities

 

It's named for the ***** river, stupid. :P

No, really:

 

now just hold on...the shift happens when oil preasure governed by the TV cable overcomes the preasure governed by the pump. so if you put it in 1st, you block that TV oil preasure from entering the system so it wont shift. if your tranny shifts, you may have a bad seal somewhere.
FYI, ive gone to about 6.5G's with my first 305 and it never shifted. besides...your tranny doesnt know what your engines redline is anyways...how can it govern when to shift?

 

Most of the stock 700-R4's WILL shift when in first. The shifts will happen as they would at WOT. It will also not allow you to downshift into too low a gear. I found this out during a panic stop and downshift at 90 MPH. Accidentally stuck it in first gear, and IIRC it only went into 2nd.

Also, the advantage of D vs. OD is that D is just a straight shot through the trans (both planitary sets locked), so there is less heat generation and wear.

 

I Have also found over the years ( just something I noticed ...not gospel) That when in town keep it in just D .... that way the tranny isn't always shifting back and forth with the little throttle inputs it takes to get around town . SO I say when in town ...keeping it in D is a bit easier on the tranny .

 

Not really, since you're driving around on the overrun clutch all the time.

 

I made an account just to tell you you're a nitwit nutjob. Have a nice day.

 

I'm sure Sonix has just been sitting back watching this thread for the past 13 years with a smug look of utter self-importance on his face. Until you came along and taught him what was what. Nice job!

 

I don't mean to be rude but your dad must have forgotten he was your dad and not your mom when he taught you to drive an automatic at all lmao. This is my 6th car and the first one that is an automatic. Some of us in this forum are men FYI

 

Anyone who doesn’t understand the concept of gearing vs acceleration (including overdrive) needs to pedal a 10 speed bicycle in a hilly area. It won’t take long to figure it out.

 

1. Converter locks in 2nd, 3rd, and 4th/OD.
2. Saaaay wha....?? What's the inner workings of the trans got to do with the fun of manually shifting it? You DO know that when manually shifting, the trans isn't "governed by oil pressure and throddle position"...it's governed by your hand.

 

Excuse me sir but not everyone has a dad like you.

 

Excuse me sir but not everyone has a dad.

 

Boy you really showed those guys. One not here since 2013 and the other since 2016.

You joined just to dig this thread up and reply to these guys that ain't been here for 7 to 10 years? WTF

 

Hmmm..I am drawing a BLANK!

 

All Transmission Models are different an have different usage recommendations, but regarding THM700-4R Transmissions and the 4L60E Family of Transmissions (60E, 65E, 70E, and 75E):

The THM700-R4 Transmission should never be used in the OD/ D4 Gear-Selector Position for Full-Throttle/ Heavy-Throttle use.
It is easy to over-power the Input-Sprag.
Use the D/ D3 Gear-Selector Position for Full-Throttle/ Heavy-Throttle use (or the M2/ D2 and M1/ D1 Positions as well).

Between 1982 through 2014 The THM700-R4 and it's Electronically Controlled Variant (The 4L60E/ 65E/ 70E/ 75E) the Input-Sprag has been Updated-Upgraded FIVE Times.
The Original Part was actually a One-Way Roller-Clutch and NOT an actual Sprag Assembly.
It was a 12-Element One-Way Roller-Clutch for 1982 ONLY.
-1983: First Update-Upgrade to a 26-Element Sprag Assembly.
-1987: Second Update-Upgrade to a 28-Element Sprag Assembly.
-1993: Third Update-Upgrade to a 29-Element "Single-Cage" Sprag Assembly.
-1995: Fourth Update-Upgrade to a 29-Element "Dual-Cage" Sprag Assembly.
-2005 - 2008: (GM has conflicting Documentation regarding this)...
Fifth Update-Upgrade to a 29-Element "Dual-Cage" Sprag Assembly with 12.7% Larger Elements.

While these Updates-Upgrades have made a tremendous difference...
My Original Statement still applies:
The THM700-R4 Transmission should never be used in the OD/ D4 Gear-Selector Position for Full-Throttle/ Heavy-Throttle use.

When the First Model of the THM700-R4 (Model-Year 1982) was designed in the Late-1970s through Early-1980s...
It only had the 1982 Corvette to worry about as far as "High Performance" Vehicles at that time.
In 1982 the Corvette Engine produced a "Massive" 200 HP and 285 Ft/ Lbs of Torque for a 3,200 Lb Car.

The Input-Sprag Updates-Upgrades have allowed for significantly more Power to be put through the Transmission, But...
Still ONLY Use the D/ D3 Gear-Selector Position for Full-Throttle/ Heavy-Throttle use (or the M2/ D2 and M1/ D1 Positions as well).

This does not apply to the 4L60E Family of Transmissions.
The Ideal/ Safest way to operate the Transmission (trying not to destroy it) is by Manually going from D1 to D2 and then to D3 for Full-Throttle/ Heavy-Throttle use.

If anyone desires to be able to use the 4L60E Family of Transmissions in the same manor as the THM700-R4...
One Aftermarket Upgrade is Required:
The Sonnax HD 2-3 Shift-Valve (Remove OEM 2-3 Shift-Valve, Drill one Hole in Valve-Body Casting, Clean, and Install Sonnax HD 2-3 Shift-Valve)
Very easy to do!

 

If it was that important to know before getting a license they'd put it in the DMV handbooks but they don't so saying "you should know this when you get your license" doesn't make sense also not everyone drives a manual

 

Thread is about automatics.

But people should know how to drive...before driving. Even manuals.

 

This thread again. I forgot this was where the guilt comes from when I annihilate my rear tires in a busy city intersection and forget to drop it in D first.

 

I love that 3 different people were so triggered by this thread that they created an account just to reply, then abandoned the forum.