Question on '96

I have the 4.10s and MMx driveshaft ready to install in the '96.

Since the '96 is OBD-II, do I need to change the speedo gear??

I'll eventually get an SCT Xcal2, but meanwhile...

It's a youngster obd II. Speedo gear is needed.

Yup I think the Gen IIs switched to a speed sensor inside one of the wheels so therefore you didn't need to change it out.

So, just to be straight, it is a model generation change and not because it's OBD-II.

Thanks.

Almost 100% positive.

There are few things in common between a Gen I and Gen II other than the "ODB II" stamp. You would be surprised.

But we're talking about differences here ? What did I miss ? ^^^^

JP, it's because of the way the electronic odo is driven in a g2.

You missed "So, just to be straight, it is a model generation change and not because it's OBD-II."

Implying that just because they are both Marks and ODBII does not indicate they are the same.....

I can't remember what ratio it's for but I am sitting here with a Black gear for a 96 Gen 1 if any one needs it.

I understand JP's comment. I can't figure out what you meant by:

"There are few things in common between a Gen I and Gen II other than the "ODB II" stamp. You would be surprised."

That's all.

Mad1stGen said:

I understand JP's comment. I can't figure out what you meant by:

"There are few things in common between a Gen I and Gen II other than the "ODB II" stamp. You would be surprised."

That's all.

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Not to interupt, but I think his statement is better understood if he had said "...There are VERY few things in common between a Gen I and Gen II other than the "ODB II" stamp. You would be surprised."

I could be wrong though.

Here is the deal regarding the transmission speedo gear. It needs to be changed on any year Mark VIII if you have changed the ring and pinion gear to anything other than what came from the factory stock.

FWIW, this info came directly from Jerry W.

Ryan has already ordered one for my gen2 with 4.10's. Thanks, Ryan and Aric!

mlschultz said:

Here is the deal regarding the transmission speedo gear. It needs to be changed on any year Mark VIII if you have changed the ring and pinion gear to anything other than what came from the factory stock.

FWIW, this info came directly from Jerry W.

Ryan has already ordered one for my gen2 with 4.10's. Thanks, Ryan and Aric!

Click to expand...

Care to explain why ?

White speedo gear is trash anyway. Have them order xcal or the teeth will end up in the trans if you're dead set on having this done.

I still don't see the need for it.

Mad1stGen said:

Care to explain why ?

White speedo gear is trash anyway. Have them order xcal or the teeth will end up in the trans if you're dead set on having this done.

I still don't see the need for it.

Click to expand...

I'm with Jeremi.

To Mike:
I heard that Rumor also... I have had the gears changed and verified with the GPS that the speedo/odometer worked correctly. No problems with shift patterns after chip either. So please elaborate.

Gen 1 OBDll Cars have vehicle speed taken from tranny (gear change) where as Gen ll utilizes speed imput from wheel sensor, which is why these models need only change the parameter in the chip (no hardware change required.

Remember the rpm dip after the 1-2 shift in my track videos that appears to be lifting off the throttle? That is one of the shifting issues that Aric was debugging in his tune for me.

From what I understand talking to Ryan, Aric talked to Jerry about it, and they came to the conclusion that the stock speedo gear in my car was sending inaccurate data to the ECU, which in turn was causing the delay after the shift. Cart before the horse scenario

I am sure there is much much more involved than my simple explanation, and installing a supercharger amplified my particular situation - especially during rapid acceleration at WOT. Point is... match the speedo gear with the rear gear to have peace and harmony with your Mark

edit: Max, My speedo is perfect and matched to my GPS too. There is much more involved than just the speed of the vehicle with this gear. It is a $14 part, and if it solves my problem, I am happy

mlschultz said:

Remember the rpm dip after the 1-2 shift in my track videos that appears to be lifting off the throttle? That is one of the shifting issues that Aric was debugging in his tune for me.

From what I understand talking to Ryan, Aric talked to Jerry about it, and they came to the conclusion that the stock speedo gear in my car was sending inaccurate data to the ECU, which in turn was causing the delay after the shift. Cart before the horse scenario

I am sure there is much much more involved than my simple explanation, and installing a supercharger amplified my particular situation - especially during rapid acceleration at WOT. Point is... match the speedo gear with the rear gear to have peace and harmony with your Mark

Click to expand...

Did the white gear fix that issue ?

Did you see the teeth on the white speedo gear ? Mike, they will be gone by the time you make it to MI. Speed cal is the only viable option if you have gears steeper that 3.73s.

Jeremi, I just found this info out a couple hours ago when I stop by the shop to pick up my video camera. I am going to talk to them about using that speed cal instead of the actual gear.

Thanks for the heads up. I have got way way too much money in that transmission to chew up that gear in there

The car works as it should unless you are really in it, and it bounces off the rev limiter. So, if I drive it normal, it runs fine.

Mad1stGen said:

Did the white gear fix that issue ?

Did you see the teeth on the white speedo gear ? Mike, they will be gone by the time you make it to MI. Speed cal is the only viable option if you have gears steeper that 3.73s.

Click to expand...

I don't want to butt in and muddy the water, but if the teeth on the white speedo gear are that fragile, mine in the '93 would've been gone quite a while ago I would think. I don't recall exactly when, but it's been somewhere in the neighborhood of 3-1/2 years and 20,000 plus miles since I changed to 4.10s and had the speedo gear replaced. The 4.30s have been in a little over a year as part of that time. I do not have a speed-cal on the car either and the car runs fine and has no related issues that I know of.

I recall it did not shift 'quite right' between the time the 4.10 gears were in and the speedo gear was changed. I never did put a finger on it 'cause it was a very short period of time.

That's what led me to ask about the '96. As it appears now, I have to change the speedo gear, like it or not. Maybe I should get an external tranny filter to address any concerns of plastic fragments?

If we want, I'll bring a new white gear to the MI meet and we can pull the speedo gear out of the '93 and compare.

One thing I know... the VSS feeds information to a lot more systems other than the speedometer. So a gear change makes sense(at least on a Gen1). And having said that, I guess I better put a speed-cal on the list since I have 4.30s.

What is not so clear is how the same information is handled in a Gen2, besides the fact that obviously the speedo gets it from the ABS. Do all systems get the speed of the car the same? If so, why even have a VSS on the Gen2.

I am not surprised it didn't shift right for you with no tune and no speedo gear changes. Both are required on a 1st gen car.

I had to replace the white speedo gear in my old 95 just after 10k blown miles. The worn teeth made the speedo act funny. They were very flimsy and waiting to break. If you run a deep search on tccoa, you'll find more failures of this kind. Talk to any high performance trans builder (not DR ; they'll tell you the same thing. Speedcal is a must if you run 4.30s as a 25 tooth gear doesn't even exist.

FYI, both of my cars are running mustang output shaft and purple gear (8 tooth instead of 7 on the lincoln), one had 3.73s, this one has 3.27s. I also felt it was common sense to replace it, but if I were to use the white Jeep gear, I'd steer towards speedcal.

Mike, does it bounce off the limiter because the trans goes into neutral ? Does the computer command the shift or not ? Mine felt the same with the DR trans in it. It's called slippage. I hope you have a different problem all together.