741 to 489

[Sat66]

Need a little help. I switched from a 741 open center section to a 489 cone type sure grip in my 66sat. Now during the dry fit the axles won't go in all the way. (About 1/2"or so is still sticking out). Before I took the 489 in, I took the drivers side axle and slid it in the 489 when it was on the bench to make sure the splines lined up. I took a tape measure, slid it in until it bottomed out, 26 3/4" and the axle was a little shy of that. So it should be good. I know the splines line up because I can turn the axle and the yoke spins. Am I missing something?

 

[moparnation74]

I am wondering about your thrust spacers....

 

[1967coronet440]

I believe the thrust blocks maybe are different if the 741 is a pre 1965, which I believe would make them non interchangeable, let me find the article for you.

 

[1967coronet440]

Here you go, as suspected the thrust blocks are probaly the culprit here.

http://www.mymopar.com/Mopar8_75RearEndGuide.htm

 

[wannadrag]

741 case was used till 72 and if the splines inside the 489 suregrip aren't line up the axle wont slide all the way in

 

[Daves69]

A half inch sounds a bit excessive (to me) as though its not getting into the inner cone.
One side goes all the way and other don't?
Did you have two axles free fitting in the SG splines on the bench at the same time or just used one and swapped it to the other side? To line mine up I needed the pair when I torqued the SG down.

 

[Sat66]

Not sure what the thrust block is, but if it's the shiny flat button past the splines I'm not even hitting that. I pulled the 489 and put it on the bench put a little grease on the splines of the axle, and slid it in. It pushed the grease up the splines about 3/8" to 1/2" up. What I noticed is that when I looked inside rear end where the axle goes i noticed a machined grove (or two piece receiving splines). Because where that grove is. Is about where the axle is bottoming out. IThis seams like it goes in up to that grove then it stops. Btw my 741 has no grove just splines all the way. Here's a pic where you can see the grove.

 

[Daves69]

What it looks like inside. The cone parts (if this is the type you have) from inside and out. All four need to be aligned at the same time .....

 

[Sat66]

Dave, now that I look at it I don't think I'm getting to the second set of splines. If that makes sense. I took the 498 in to a reputable speed shop and had new gears and bearings put in, I'm waundering if I should have sent the axles with. So now what do I do.

 

[Sat66]

Do I need the axles in when adjusting/torquing?

 

[Fran Blacker]

I had the same problem. Mine was a clutch type, one of the side gear didn't line up. I'd take third member out and look to make sure spline line up. Then measure how far axles should go in. Wrap a piece of tape around where axle would be fully seated. Make sure it bottoms out.
If you get them fully seated measure the distance from plates that holds axles in so if it's still to width as 67Coronet 440 said.
I had to make a rig to turn sure grip to line up splines without ripping it apart.

 

[Daves69]

If you have a torque wrench and a pair of axles you can re-align it.

Check this thread ....
http://www.forabodiesonly.com/mopar/ams/how-to-recondition-a-sure-grip-cone.28/

 

[Fran Blacker]

To re-align it without taking it apart. You need to hold the yoke so it won't turn. You need to figure out a way to turn the axle that doesn't line up. I took a 6' piece and craved it so I could go over 2 wheel studs. Use 2 mag wheel lugs as not to damage threads. After I had it setup it took 3 tries before they lined up. Turned axle a little tried, repeat until they go in. This thread will show you what I did.

http://www.forbbodiesonly.com/mopar...-what-did-i-miss.118765/page-2#post-910527275

 

[moparnation74]

Or if the speed shop is not out of our way take that and the axles and have them do it....

 

[Cranky]

I have a pair of T handles made from an old pair of axles that I use to assemble on. Can also use them to check how tight a SureGrip unit is....

Stand on the bottom T and grunt on the top one.

If you don't take it back to the shop that assembled it, you can do what Fran said. Been there done that too.

 

[Sat66]

Guess what, the damnedest thing happened it's all back together. My buddy and I had the center section on the bench and with the axles, and with a Little jockeying around they slid in. So back under the car we went to dry fit again. Every thing went back together without a hitch. We pulled it apart sealed and gasketed everything, and had to adjust the rt. axle. Both axles have a little play, and I think we're all good. I have no idea what happened the first time, but I really appreciate all the help and input. You guys will be the first to know if anything goes wrong on the test run. Thanks again everyone.

 

[Cranky]

Guess what, the damnedest thing happened it's all back together. My buddy and I had the center section on the bench and with the axles, and with a Little jockeying around they slid in. So back under the car we went to dry fit again. Every thing went back together without a hitch. We pulled it apart sealed and gasketed everything, and had to adjust the rt. axle. Both axles have a little play, and I think we're all good. I have no idea what happened the first time, but I really appreciate all the help and input. You guys will be the first to know if anything goes wrong on the test run. Thanks again everyone.

The clutch splines could have been off just enough the first time to keep things from sliding together easily. And the axles are supposed to have a bit of play .008 to .012 iirc. It'll be listed in a repair manual.