Thread: did i make my car even slower??

Originally Posted by Turbocharged400sbc

RockAuto shows the 2011 Lucerne having the black chain scoop which is the 293 scoop. you are now a 2.86 ratio

Clicking on the cross reference of other vehicles it is used in (click on the part number), you see a multitude of cars we know 100% had the 35/35. One example is the 97-08 GP. I'm thinking there's something else going on besides color.

just got back from a drive and gps shows my speedometer is still accurate.

Then it's placebo and life is good.

Smile and drive on friend

im on a facebook group and overkill had this to mention

"You'd get a firm shift if it was the wrong ratio, I'd also be able to tell on a scanner. If you swapped the diff, you should be back to 3.05. I cuoldn't think of a non-hd 65e off the top of my head that didn't come with 35/35 drive chain gears."

Originally Posted by BillBoost37

Then it's placebo and life is good.

Smile and drive on friend

im at 3:05 gear ratio you think?
but what i find weird though is that my rpms are different like at 60km/h im at 4000rpms now instead of 5000rpms, and at wot 1st gear bring me a little over 90km/h and it used to be 80km/h.

You replaced a bad transmission right?

Smile and drive on.. the old trans was hosed. Either that or you are looking at US RPM's vs Metric RPM's (yes..now I'm just messing around).

If the speedo is dead on, the ratio is right.

lols you are right the trans shifts 1000x better.
I am getting a retune on saturday(for er rockers and l67 HVTB) so ill get overkill to check if its all good, ill come back to this thread an update you guys.
thx for all the help and information.

He will look at the calculated 3rd gear. It should be 1:1 and he'll know you are all set

awesome.
we need the like button back lol.

But you know..

You swapped the diff
You checked GPS

The only thing you don't like is that you are thinking it should shift the same as a dying trans and it doesn't. FWIW if the pcm was pissed about the gear ratio, you would know. It wouldn't be a firm shift as Will mentioned, it'll be a BANG into gear like it's trying to rip itself out of the engine bay shift. There would be no doubt in your mind that something was very unhappy.

well that makes me feel better, car shifts buttery smooth and it has the transgo kit as well so like you said if it wasnt happy itd shift really hard.
thanks, id be stressin about this all week lols.

Wait.. back up. Maybe we forgot something (wink wink..)

....

well got the verdict
BAD NEWS: this new trans has 2:78-76(cant remember that exact #) gears........ Im so pissed lol. i put in my 3:05 fdr so idk what kind of sprockets would make it suck a low gear ratio.... overkill was also stunned said he never saw anything like it.

Soooo toss in a GT set of 3.29 to bring it back up.

There's only three possibilities in this trans TMK. But..and big but here, I don't know the newest transmissions.
You could have drive/driven
33/37 =.89 * gear ratio of diff
35/35 = gear ratio of diff
37/33 = 1.12 * gear ratio

So if you have 2.78 coming out then likely you have the top ratio of gears with the 3.05 ratio to give you 2.72 roughly.

Still only finding references saying that trans is a 2.86 from the factory. Which should be a 2.86 diff only. You still have the diff right? Count the number of teeth on the sungear (one that slides into diff)

Also.. do you have a picture of the tag on the trans?

no pics of the tag on the trans, I have the receipt lying around somewhere if that helps.
ill count the teeth after my morning coffee lol.
it couldnt be a 2:86 diff though cause if my 3:05 is in it would be 3:05. and if we accidently thre the 2:86 back in it would be 2:86 not 2:78.
say it is a 3:29 I have sitting in the shed, if i slap that back in It will only bring me back up to 2:86 correct? still way to low for my liking. I miss my intown grunt I used to have with the 3:05, what id like to do is dig into the old trans, pull the 35/35 out and slap it in the new trans with 3:29, hoping to have that done before summer ends and take it to the track and see if it can break into the 14's

The 3.29 would bring you to 2.93. Seems that this trans has the 33/37 set in it.

You can swap that in the car, the one snap ring that holds the drive gear to the input shaft will be the worst of it. And the right tools will make it pretty reasonable.

but then i need it tuned again and overkill is heading back to B.C so ill have to send my pcm for the gear change... so I really just want to grab the 35/35 out of my old trans and buy the 3:29 and slap it all in, with all my mods in my sig i think 3:29 would be a great boost for the low end power. then my n/a build is pretty much done cant think of anything else worth doing to it.

does the new trans have to come right out of the car to swap the drive/driven gears?

No

You can do it in the car. You would follow the 4th clutch hub replacement write up. That will bring you to the same spot you need to be at to swap the gears.

Here is what things look like when you do all that the write up gives you and the 4th hub is out. This one was out of the car, but can be done in the car.


On the gear to the left is the Input Speed Shaft reluctor wheel. That lifts right off and then you are looking at the chain and gearset. Unfortunately you can't see the clip at the base of the shaft in this pic.


The gears look like this




As James had said earlier about the white lube scoop, you'll want to change that as well. Here's where it's located


Out of the trans