489 Case information please.

[davidplymouth1@]

Any thoughts on the YUKON 489 case? I'm having a hard time finding a 489 to build. Looking for a .355 gear sure grip/ posi w/ 1350 yoke. I know the 1350 is not standard for chrysler but it's how I've always done my performance cars. Any info on the yukon would help. Like do they use a crush sleeve? Any quirks or short comings ect. Thanks to all

 

[493 Mike]

Have you priced the difference between what you are proposing and a aftermarket 60?
Far stronger and better resale $.
Mike

 

[33 IMP]

I bet Dr Diff will have anything you need, and Cass (the Doctor) will answer your questions.
Heartily endorsed by almost everybody here.

 

[67plysat]

I used a Yukon 489 case, other than having stronger looking side adjusters I couldn't tell much difference from the original 489 case. No quirks or shortcomings that I could tell, no problems after several thousand miles. I used a solid spacer instead of a crush sleeve.

 

[davidplymouth1@]

I bet Dr Diff will have anything you need, and Cass (the Doctor) will answer your questions.
Heartily endorsed by almost everybody here.

Thank you - I spoke with Cass already - but was confused by some of the info I got there. Dr, diff kept saying theirs was the best - which is what every salesman says. And kept saying to compare his against the Yukon version at his web site (because he sells both) but there is no "side by side" comparison at his web site. You can look at the yukon on one page and the other on a different page but there's no side by side comparison at Dr diff. It's impossible for me to tell just by looking at two different pages. So other than a salesmans' word - I still have no comparison or stats to examine. His following on you tube is very positive too - but no reviews on his 489 builds yet. Not for the yukon or his super duty 489. Prices are competitive with my local guy. But my local builder says - better to build an old Chrysler 489 than a new yukon. Apparently - he's not a yukon fan or he want's me to buy the used case he has at his shop already. Its' a big investment for me, and I want to learn as much as possible before buying anything. Thank you for taking the time write. I appreciate it very much.

 

[davidplymouth1@]

I used a Yukon 489 case, other than having stronger looking side adjusters I couldn't tell much difference from the original 489 case. No quirks or shortcomings that I could tell, no problems after several thousand miles. I used a solid spacer instead of a crush sleeve.

Thank you for the info - I did not know about the side adjusters looking stronger. It was very helpful. You're the first contact I've made with an actual Yukon owner/ user. Thank you for taking the time write. I appreciate it very much. Have a Great day!

 

[5.7 hemi]

Either one will do just fine. The Yukon has a “Y” cast into it on the outside. I wouldn’t have a problem with setting up either one and running it.

 

[kiwigtx]

The Yukon nodular case claims to be stronger and slightly longer from what I recall......I nearly bought one a few years ago as I was having trouble finding reasonably priced used factory units.

 

[davidplymouth1@]

Have you priced the difference between what you are proposing and a aftermarket 60?
Far stronger and better resale $.
Mike

Thanks. I did not know that you could bolt a dana 60 in an 8.75 rear housing. I thought a dana 60 had a rear inspection and a different bolt pattern for the center pumpkin - Would I need to change the axles?

 

[33 IMP]

Thanks. I did not know that you could bolt a dana 60 in an 8.75 rear housing. I thought a dana 60 had a rear inspection and a different bolt pattern for the center pumpkin - Would I need to change the axles?

No, a dana 60 is an entirely different rearend. I think what he is saying is that if you consider all the expense of a new 8 3/4 center, a crate dana might be a good alternative, especially for a powerful big block car.
If you already have an 8 3/4 housing and axles, and breaking it with too much power is not likely, building a new 8 3/4 center is probably the better, cheaper choice.

 

[davidplymouth1@]

Oh, Ok, I get it now. I thought it was clear that I already have the axles and housing. That's why I'm looking for a 489 to build. I broke the guts out of the current 742 and I hear the 489 is the strongest for an 8.75 housing I think it must've broke because it was old. It's just a small block. I'll look into a crate dana rear if costs are comparable to building a 489 center. thank you for the advise - I just assumed a complete dana would be at least a few thousand bucks.

 

[5.7 hemi]

They are, don’t be standing up when ya see the price.

 

[33 IMP]

I would guess that an assembled all new 489 case center with a true track will run around $1500, maybe $1200 with a clutch suregrip. (I'm guessing an 8 3/4 will cost more than the more common 9" ford)
I think a new Strange/Dr Diff 60 will run around $2500-$3000, depending on brakes and suregrip choice.
If you are not racing your small block with a stick, and slicks, 8 3/4 should be fine,

 

[davidplymouth1@]

No, a dana 60 is an entirely different rearend. I think what he is saying is that if you consider all the expense of a new 8 3/4 center, a crate dana might be a good alternative, especially for a powerful big block car.
If you already have an 8 3/4 housing and axles, and breaking it with too much power is not likely, building a new 8 3/4 center is probably the better, cheaper choice

No, a dana 60 is an entirely different rearend. I think what he is saying is that if you consider all the expense of a new 8 3/4 center, a crate dana might be a good alternative, especially for a powerful big block car.
If you already have an 8 3/4 housing and axles, and breaking it with too much power is not likely, building a new 8 3/4 center is probably the better, cheaper choice.

Yeah - I just checked - a new crate dana 60 from MOSER is well over $4000. There is no comparison on which would be the cheaper way to go. You're right. It's way cheaper to just build a nice new 489. I doubt it'll ever break again. I think that 742 was just old. Actually, the 742 case is still good - I just hear the 489 is stronger - and as long as I'm rebuilding it anyway - why not use the 489. I just wasn't sure about the Yukon brand - but so far I'm hearing very good reports about it. I'm still shopping, but it's probably what I'll do. Thank you for your input.

 

[33 IMP]

A 741 case has an undeserved rep as the weak sister, and imo, a 489 is not significantly stronger than a 742. IF you can find a 742 gearset in the ratio you want, and IF your 742 case wasn't hurt, and IF your suregrip is in good shape and intact, I'd certainly save the expense of buying a 489 case. ( this from a guy running a 500hp 440 thru a 742 case with stock axles and slicks.)
I DO think a new case is a good idea. If you want one, go for it.

 

[33 IMP]

Check out Dr Diffs comparison of the 741, 742, and 489 pinion stems on his website. 489 stem is bigger on one end than the 742, smaller on the other. And the weakpoint on the yoke end is identical on all three versions.

 

[davidplymouth1@]

I would guess that an assembled all new 489 case center with a true track will run around $1500, maybe $1200 with a clutch suregrip. (I'm guessing an 8 3/4 will cost more than the more common 9" ford)
I think a new Strange/Dr Diff 60 will run around $2500-$3000, depending on brakes and suregrip choice.
If you are not racing your small block with a stick, and slicks, 8 3/4 should be fine,

Thanks. Never raced it. I do romp on it. 727, 3800 stall 12" x 27 Mickey Thompsons. It pulls ok - but no racing

 

[davidplymouth1@]

A 741 case has an undeserved rep as the weak sister, and imo, a 489 is not significantly stronger than a 742. IF you can find a 742 gearset in the ratio you want, and IF your 742 case wasn't hurt, and IF your suregrip is in good shape and intact, I'd certainly save the expense of buying a 489 case. ( this from a guy running a 500hp 440 thru a 742 case with stock axles and slicks.)

Huh - Ok. I'll look into that. The clutch pack broke apart and the ring and pinion were damaged as well. But the case looks fine. I think it was probably just old. I never had it apart as long as I've owned it. Just changed the fluid one time about 4 years ago. The fluid looked ok, but never saw inside it. So, it could've been bad and I didn't ever know it.

 

[davidplymouth1@]

Huh - Ok. I'll look into that. The clutch pack broke apart and the ring and pinion were damaged as well. But the case looks fine. I think it was probably just old. I never had it apart as long as I've owned it. Just changed the fluid one time about 4 years ago. The fluid looked ok, but never saw inside it. So, it could've been bad and I didn't ever know it.

Thanks much - Chrysler is rather new to me. I've been building GM's most of my life. Appreciate the advice and info very much. Chrysler is a strange animal. LOL

 

[451Mopar]

Bump this so I remember to check the parts this weekend.
Over the last year I bought a Richmond 3.55:1 gear set from Summit, and a rebuild/Install kit with solid spacer from Dr. Diff.
I was planning to put it in my old 3.23:1 sure-grip 489 case.
The gears were on back order for several months, and I got a few extra $$$ in the meantime, So I decided to just build a new center section with a new 489 case which I think is a yukon? (I'll have to check), and the "sure-track II" differential from Dr. Diff.
When I looked over the "sure-track II" there are no markings on it anywhere of any kind to identify part number or manufacturer. I was trying to find the torque-bias rating, but I guess I would need to call Cass and ask him?