Validation question on my roller

[yahrt]

Making good progress, brakes bled with a nice firm pedal, just dropped to the ground for the first time and am somewhat surprised with how much effort it takes to push the car around, the tightness is in the rear end, I presume that is simply the nature of these cars, but i can push my GT500 at 4000 lbs when in neutral with ease...normal?

[Papa]

If the wheels all turn freely when the car is in the air, think rolling resistance and toe in at this point. If things don't move freely with no weight, double check brake installation.

[edwardb]

Something isn't right. I can push mine around the garage in neutral with ease. No reason for these cars to be any different than any other. If your alignment is way off, could see that affecting it I guess. But it would have to look really wonky IMO. Sounds like you maybe have brakes dragging. Just a guess though.

[yahrt]

Ok, let's back up to the Moser rear end straight out of the crate, hand turning the input shaft was all but impossible, hand turning the axles was doable with both hands and significant effort, does that seem normal/abnormal?

[Papa]

Ok, let's back up to the Moser rear end straight out of the crate, hand turning the input shaft was all but impossible, hand turning the axles was doable with both hands and significant effort, does that seem normal/abnormal?

Did you add fluid to the diff yet?

[yahrt]

yes, Lucas 85w-90 HD gear oil + friction modifier, ~ 2 quarts total

[rich grsc]

Ok, let's back up to the Moser rear end straight out of the crate, hand turning the input shaft was all but impossible, hand turning the axles was doable with both hands and significant effort, does that seem normal/abnormal?

That doesn't sound right.

[Jeff Kleiner]

Ok, let's back up to the Moser rear end straight out of the crate, hand turning the input shaft was all but impossible, hand turning the axles was doable with both hands and significant effort, does that seem normal/abnormal?

Not normal.

Jeff

[yahrt]

Hmm, i just called Moser tech support and they said it was normal and would loosen up with use...I guess next step will be to call FFR when they open up again

[NAZ]

As a Ford Service Tech I've rebuilt many Ford rear ends. You should be able to turn the pinion by hand with some resistance oil or not, if it is "all but impossible" to turn without the brakes installed that indicates there is a problem. The pinion bearing pre-load spec for new bearings is 16-28 inch pounds of turning resistance. There will be a bit more once the carrier and axles are installed but still easy enough to turn by hand, certainly no where near "all but impossible". If the pinion is hard to turn as you described AND the brakes were not installed, contact the builder to coordinate a return for inspection / repair. Do not run it in this condition -- it won't heal itself and it won't "break in and then run smooth" like some will likely tell you.

BTW, I purchased a Moser 88 and it was not especially difficult to turn the pinion. Unless your definition of all but impossible is an exaggeration, I call BS on Moser's advice to run it like it is.

https://performanceparts.ford.com/do...htM-4209-8.pdf

[yahrt]

Thanks for all your comments and suggestions, wish I had posed the question earlier, i was somewhat suspicious when i first received the rear end but attributed it to the small diameter of the pinion and poor leverage, thinking wheels would dramatically improve things, I will back up and get it taken care of.

[Jeff Kleiner]

As NAZ said a rear end will not "wear in". It might eat itself up though...

Jeff

[EZ$]

Contact FFR through their "info@" email. I sent a question a week or so ago, and Tony responded the next day, so they are monitoring the emails.

[MSumners]

Clearly the least experienced responding here and would put more stock in the above responses. However, any chance your E-brake cables are being compressed when there is weight on the rear suspension due to their course near the control arm?

[yahrt]

I wish that was it but they are not currently connected

[yahrt]

back to my problem outlined above, with my car on jack stands and the wheels on, it takes about 55ft/lbs of torque to turn the rear axle when using a socket on one of the lug nuts, i would be grateful if some of you could run the same test on your car and post a number to see how mine compares, thanks

[yahrt]

should have also specified that the driveshaft is not connected

[NAZ]

It would actually more informative if you could determine the torque required to turn the pinion with the wheels off the ground. It does require using a dial type torque wrench that most folks don't have but you may be able to find a loaner. That way you quantify the amount of torque rather than a perceived notion of what it takes to turn the pinion. I would take that info back to Moser, you might even ask them first what is the max allowable on one of their axles before you share.

Remember, the max torque required to turn a properly pre-loaded pinion is 28 inch pounds. Adding the friction of the ring gear, carrier bearings and axle bearings & seals will increase that required torque and I don't have a spec for that and none exists to my knowledge so you have to use experience to determine what seems reasonable.

As an after thought, I should have converted inch pounds to foot pounds for you as most never work with inch pounds and may be more familiar with what foot pounds feel like. 28 inch pounds is equal to 2.3 foot pounds.

[rich grsc]

back to my problem outlined above, with my car on jack stands and the wheels on, it takes about 55ft/lbs of torque to turn the rear axle when using a socket on one of the lug nuts, i would be grateful if some of you could run the same test on your car and post a number to see how mine compares, thanks

That sounds like brake drag.
Your first explanation made it sound as if this problem existed before you assembled the brakes. Is that true? Take the rear tires off, remove the brakes, then see how difficult it is to turn the axles. You can redo you measurement with the tires off.