Rear end differential change problems

[The_Handier_Man1]

From: LJ-TJ  (Original Message)
Sent: 6/26/2008 7:59 PM

OK Boys need some help here. I just purchased a rear end in order to fix the one that was ruined when the axel departed the rear end housing when she was being towed home. Stamped on the yoke is "Detroit". On the housing is cast a letter "B" as well as C34835 all so on a tag that is attached to the Cover is 419 and below it are the numbers I think 156. I think the rear end is a Spicer 70 but I'm not sure? The universal that is on my driveshaft is smaller that the yoke I'm replacing. Is there any chance I can take the yoke off the replacement rear end and replace it with the one that is currently on the rear end that I'm taking out.



From: denisondc
Sent: 6/26/2008 9:05 PM

I hope someone who knows can answer you. I have no idea. You might have to be the one to write the book here.



From: bluebird5750
Sent: 6/29/2008 11:34 AM

They make all kinds of differant u joints. They are called b-stardo joints. Napa stocks lot of differant joints, if they don't have it they can get it for you. i've ran chevy shafts and ford rearends, pontiac shafts and chevy rearends. Never had a problem buying a joint that would work.

Chuck



From: ontheroadagain7
Sent: 6/29/2008 12:56 PM

You can if the pinion shaft and splines are the same. The problem you will have is getting the pinion bearing preload (backlash) set correctly, normally I  count the threads and mark the nut so it ends up in the same place when you tighten it up,that is using the same yoke. You will have to compare depth of the yokes to see if you can use the same marks as the original yoke.You can also set it up by feel before removing the yoke measure and mark how much backlash the pinion gear has.(how much the yoke turns with the axles locked ) then install the new one the to get the same amount NOTE you are better off to be a little loose then you can tighten it some more, there is a crush sleeve that sets the pinion depth and if you tighten the yoke too far you will change the pionion depth then you will have to get a new crush sleeve and set up the pinion gear. I would get a new pinion seal while you have the yoke out , you will have to get a seal that fits the yoke you are using if the dia. is different



From: bluebird5750
Sent: 6/30/2008 8:58 PM

That's why I mentioned the u joint change. Much easier and it probably needs one anyways.

Chuck



From: ZR91
Sent: 6/30/2008 9:11 PM

Randys ring and pinion has a decent spotters guide...

http://www.ringpinion.com/

Or, take some pics and post them, I am sure someone here will recognize it.

Jay

[Wayne Thomas]

Has anyone ever changed the rearend to a lower number . To try and get better gas mileage ?

[gadgetman]

It really is not that simple. Lots of factors like the trans ratio in different gears. You lower the # on the rear end and it a taller gear/less rpm. The engine may be at a point that its lugging due to the wrong rpm for the load and sweet spot on the engines torque curve.


A good running carb rather have fuel injection dist advance system working properly and driving habits are likely the best you will get in improving mileage. Also watch the weight you put in the coach,,, HA HA HA and I talk of weight and I carry everything !


I only rate my coach by "the hour" not the mileage !!!! That would be about 30.00/hr right now ! Thats pulling a car and running a genset.

[Froggy1936]

If you are investigating that route. A two speed rear setup would be worth investigating  Frank