Problem with 9" rearend

[Northwood Cobra]

When I bolted up the third member everything was fine untill I tightened up the yoke for the drive shaft, when I did the whole rearend got very hard to turn. I realize I should have replaced the crush sleeves but is there something else I could be doing wrong to make it bind up like it did?

[blykins]

Do you have a solid bearing spacer instead of a crush sleeve? If not, the crush sleeve needs to be replaced.

Also, how tight are you tightening your pinion nut (what you're calling the yoke)? Remember, it's only like 15-20 in-lbs. Not very tight.

[John Poling]

I had this same issue on mine when originally put together, I checked around and was told that it was normal to have it tight and hard to turn. As a note though, absolutely everything in mine was 100% new other than the case itself. I was told to drive it and it will loosen up. I run full synthetic with the Ford additive and now with about 800 miles on the clock it turns relatively easy by hand.
As far as the crush sleeve issue, any time you have the pinion out it is my understanding that it is mandatory to replace the sleeve as it is what puts the proper preload on the assembly.

John

[blykins]

I too have all new parts including a new Strange case...but I can turn it fine by hand. It spins very freely.

Yes, it's mandatory to replace the crush sleeve everytime. The easiest way is to just buy a solid crush sleeve or sometimes called a solid bearing spacer to use. Then you can reuse it because it doesn't crush.

Northwood: What was your backlash? Also, are the gears covered with gear oil when you turn them? That could make a difference too...

[zipzip]

blykins: be careful that you are talking the right torque - 15-20 in-lb is the "rolling torque" of the pinion shaft. The nut is actually tightened pretty tight - somewhere around 175 ft-lb.

Having it get tight may not be all that bad - the bearings are set in preload and will be somewhat tight to rotate - that's the 15-20 in-lb. If it is too tight, there is a problem.

The crush collar is what provides the preload to the system. With the solid spacer, the bearings should be measured and the spacer made the correct length to provide the preload. This spacer is then a matched part of that bearing assembly and if the bearings are replaced, the collar will have to be either replaced or remachined to provide the correct preload.

Get out a torque wrench (in-lb) and see how much it takes to rotate the pinion. Either that, or a fish scale at one of the yoke holes. Measure the radius of the hole from the shaft centerline and multiply that times the scale reading as you rotate the pinion. If you're way more than 20 in-lb, you'll have to investigate and probably replace the crush collar.

If you're close on the preload, driving may help because the gear forces "crush" the collar just a little more and end up with a little less preload. The danger is that if you are too tight, the bearings will generate a lot of heat and could burn up. If you are going to do this method, I'd suggest just doing a trip around the block, but try to put as much load on the back end as possible (i.e. several fast starts, downshifts). Get out and check the heat in the 3rd member, then pull off the driveshaft and recheck rolling torque and that the yoke nut is tight.

Hope this helps.

[blykins]

That's a good point about the soild crush sleeve...I got all my gears, bearings, pinion spacers, etc...in the same Richmond kit.

Thanks zip for pointing out the difference between the drag torque and the actual nut torque. I guess I wasn't too clear in pointing that out in my question.

[Northwood Cobra]

Wow! Thanks for all your help guys, this is great! I'll get to work on this and get it right this time. When using a solid sleeve is there any info on what the length the sleeve should be or is it measured against the length of the pinion shaft. If it's measured, from where to where should I measure.

Thanks Again!!

Terry

[blykins]

Well Zip had a good point about spacer length, but all the ones I've ever ordered appeared to be the same length....

Who made your gearset? When I ordered my ring and pinion from Richmond, I ordered the big bearing installation kit as well from Richmond...and all the bearings, shims, gaskets, pinion spacer, etc... came with it.

You can order the spacer by itself from Jegs...part #: 836-04-0011-S

It's the very same one that I ordered when I swapped cogs in my Mustang GT 8.8". In fact, the description says it fits both 8.8" and 9" Fords...so I'd say you'd be fine with it.

There's a lot of guys on here with a ton more knowledge than I have...but if it were me, I'd just order a new pinion spacer, shove it between the bearings, press it all back together on the pinion...then check your pinion depth and backlash. I honestly don't think you'd have a problem with it...but like I said, I'm not the sharpest knife in the drawer.

Hope this helps.

[zipzip]

Here's an exploded view that may help you out: http://www.texracing.com/ford_9_exploded_view.htm

When replacing a crush sleeve with the solid spacer, you must also use shims to make up the difference in machining for all the parts involved. Jeg's sells both the raw spacer and the "kit" with the shims included. Some places also sell a spacer machined to a certain width which you must supply. Unless you really abuse the car in terms of rear end load (lot of drag, running slicks and a torque peak most of the time...), you will probably be better off with the crush sleeve. It is a lot less complicated to install. To get really serious, the proper way to set up the spacer is to take some precision measurements of the parts, or assemble with known end play and measure the proper spacer width from there.

I'd say that if you want to use the spacer the "down home" method of getting it right is to have the spacer kit (with shims) and starting with just a few shims on top of the spacer (or maybe none), assemble and check rolling torque. Keep adding shims to reduce the rolling torque until you get it right. Remember that the bearings must be fully seated and rotated to properly get a reading. Also, pulling the outer cone on and off the shaft will be a pain. You'll have to block up the seal housing and press/dead blow the shaft out.

As far as measuring, you need to end up with measuring the "gap" that the spacer will fill, and then subtract about .001 to .002 (guess) to get you to the proper preload. I'd say a depth mic from the outer face to the inboard bearing cone with the outer bearing removed will give you one side. Then measure the depth from the outer face to the outside bearing cup shoulder and any offset between the bearing cup face and cone face. Voila! Easy as 1,2,3.....not.

[Woodz428]

zipzip beat me to it, when I read the 15-20 inch pounds I knew it was way to low but got beat out on the post. That would have made for a short lived gearset.

[blykins]

I meant well...I just wasn't very clear in the words I used....

[Northwood Cobra]

Called my tranny guy, he's letting me trade the rebuilt t-5 for a new tko or 3550. For an additional upcharge of course, but at least i'm getting what I need now.

Thanks for all your help guys!

Terry

[Northwood Cobra]

Okay wrong place to post that reply, that was for the tranny guys who helped me. But I am getting the rearend straightened out as well.

Thanks to all

Terry