exchanging center sections?

[Crazy440]

I've ordered a 8 3/4 center section with 2.94 gears.  I'm running 4.30s, now.  Need something a little more suited for the highway, from time to time. My question is. once set-up, is it just a matter of pulling the axles and switching back to the 4.30s, when I want to have some fun. axles have green axle bearings. Anything else? (I know refill fluid, etc.)
Thanks

[mvandale]

Did the same thing recently: swapped from 4.10 gears to the full-highway 2.76s.  The center sections & axles I believe are interchangeable.  However, the only thing you'll need to check is the u-joint size in the differential/pinion yoke.  There are two types: small & large.  If you swap center sections with a large/small u-joint size yoke and it isn't the same as the diameter of the u-joint in your driveshaft, it won't bolt up.

I can't remember the exact diameter differences (lots of easy info to be googled), but one option is just to get a different yoke to match up with your driveshaft u-joint diameter.

BUT if going the option of changing the yoke, also keep in mind that there are two different pinion yokes (besides the u-joint diameter size): fine spline & course spline.  In any event,  there are usually plenty of them available on eBay.

Sorry if I gave a confusing answer.

[oldcarnut]

Getting ready to yank mine for different reason.  Don't forget to have on hand an extra gasket and the correct speedo pinion to match your tire/gear ratio.

[Chryco Psycho]

Very straight forward , pull the axles  & drop out the carrier .
you need a new gasket & I use ultra black silicone to seal it , you may have to remove the floater inside the gearset though with the green brgs , often the axles sit a little deeper in the housing with green brgs .
It works best if you have the same size yolk for both gearsets but you can get a conversion joint from precision to adapt the u joint if the sizes are different .
the speedo pinion is the other swap , by jacking up the rear of the car & leaving the front on the ground you will not lose a lot of fluid when you pull the adapter out

[Crazy440]

Thanks, everyone, for the info.  I'd totally forgot about the speedo.

[resq302]

Neil,

What is the easiest way to figure out what speedometer gear you need?  Our chally is running fast (reading higher speed than what you are going) and we would like to get it so it is correct.  I know the radial tires we have on it are smaller than the original F70-14s.  Is there any kind of chart or conversion formula?

[c00nhunterjoe]

http://www.moparts.org/Tech/tech/pages/speedo.html

[Chryco Psycho]

Mopar made it simple , rule of thumb is 3.23 gear use 32 tooth
4.10 use 41 but it can be off by one tooth depending on tire height

[resq302]

good info!   thanks

[Ghoste]

And should you pull the axles all the way out, be very careful not to nick the seal at the end of the tube.

[Scaregrabber]

Yup: Just pull the axles out enough to clear the centre section. I also match the speedo gear to the gear ratio, it's generally within 2% or 3% that way. 27 for a 2.76 etc.

Sheldon

[tan top]

 what other guys say  

also if your wanting to remove the axle shafts , with out any chance of seal damage , what i do is  , roll  paper round the axle shaft  after pulling it out sufficiently  , then slide that down through the seal , then pull axle out through it   , installing same

[AKcharger]

I did mine for the same reason. Here, even has pictures!
http://www.dodgecharger.com/forum/index.php/topic,2077.msg25937.html#msg25937

[John_Kunkel]

Mopar made it simple , rule of thumb is 3.23 gear use 32 tooth
4.10 use 41 but it can be off by one tooth depending on tire height

That works with a 26.2" tire.