Dana 30 do it or dont

[JohnX]

Jay I did a very light truss over the top of my 30. I made it parallel to the face of the cover, flush with the face. Then I welded a small piece onto my cover plate that sticks up about an inch over the housing. I did NOT weld to the case, only to the tubes. Then I bolted the cover on AND bolted it to the truss with four bolts over the top. Effectively I connected the case to the truss without having to worry about welding different materials. Wish I had some pics for you, maybe i'll snap some this week.

 

[Mr.OverKill]

with the heat and slow cool, i welded on the rear D44 with wire and it is a definite cast iron dif, i heat, weld, needle gun peen the weld then heat with a torch again then weld again and repeat...... the heat i go to is approx 450* to 500* and have never had a problem and using the grinder for spark identification the disconnect is cast as well as the dif ( but it is always better to error on the safe side in case i make a mistake, i will go test my dif again this saturday to be sure ) and definitely the knuckles are cast steel

and yes, i am a professional welder

i did the grinder test again, the sparks indicate that it is cast iron, small orange sparks just like the cast iron on the D60

 

[asp]

Jay I did a very light truss over the top of my 30. I made it parallel to the face of the cover, flush with the face. Then I welded a small piece onto my cover plate that sticks up about an inch over the housing. I did NOT weld to the case, only to the tubes. Then I bolted the cover on AND bolted it to the truss with four bolts over the top. Effectively I connected the case to the truss without having to worry about welding different materials. Wish I had some pics for you, maybe i'll snap some this week.

i've seen 14B and 60 trusses like that. good idea, i know what you're talking about... like this? (google image search 14B truss)

mr. overkill, i assume you're talking about the grinder test on the 30 pumpkin?

 

[Mr.OverKill]

mr. overkill, i assume you're talking about the grinder test on the 30 pumpkin?

yes sir i am, i know with out a doubt the dif on my D60 is cast iron ( i cut tons off of it when i got it and the oxy accy torch would not touch it but it cuts the cast steel ) and the sparks from the 30 and 60 pumpkins are the same.

 

[JohnX]

i've seen 14B and 60 trusses like that. good idea, i know what you're talking about... like this? (google image search 14B truss)

mr. overkill, i assume you're talking about the grinder test on the 30 pumpkin?

VERY similar. I made mine fit much nicer, but thats the concept.

 

[slcpunk74]

I welded my d30 diff with mig. I could not find my little torch and I was out of gas for the oxy setup so I just burned it in and put an old welding glove over it to keep it warm. I needed something in a pinch and it works so far so good. I plan to add some gussets and what not to it and be much more careful just so it is as strong as I can make it.

 

[XJEEPER]

Didn't weld my T&T truss to the diff, just to the tubes. Sorry for the inversion, I didn't take any pre-install shots of it upright.

Gusset on Inner C-lower. I fabbed my own, Skullvarian-style

Gusset on inner C-Upper

Build thread, hope this helps.
http://www.naxja.org/forum/showthread.php?t=913774&page=2hread, hope this helps

 

[IslanderOffRoad]

that is one beautiful dana 30 XJeeper.

The TNT Truss works ok without welding it to the diff? No affect on the UCA mount?

 

[XJEEPER]

Thanks.
You chop off the stock UCA mounts, as the truss comes with new mounts already installed.

 

[IslanderOffRoad]

Thanks.
You chop off the stock UCA mounts, as the truss comes with new mounts already installed.

Does that UCA mount seem weaker than stock though as its not welded to the pumpkin?

 

[ryurabbit]

Thats probably what I will do then is bracket it to the cover. I did mig weld the upper c reinforcements without a problem. I guess well see if its good enough!!:bunny:

Jay I did a very light truss over the top of my 30. I made it parallel to the face of the cover, flush with the face. Then I welded a small piece onto my cover plate that sticks up about an inch over the housing. I did NOT weld to the case, only to the tubes. Then I bolted the cover on AND bolted it to the truss with four bolts over the top. Effectively I connected the case to the truss without having to worry about welding different materials. Wish I had some pics for you, maybe i'll snap some this week.

 

[XJEEPER]

Rabbit,we're talking cast center section VS forged knuckles here.

John, I don't see where the UCA mount on the T&T truss is any less strong than the factory one that is cast into the diff. The truss is 3/16 formed steel and the UCA mount is welded on all sides.

Could there be some lateral deflection in the truss above the diff, because it's not welded to the center section? Perhaps.

Is it enough to negatively effect the handling or be point of failure? :dunno: Never heard of one failing yet.

I've had my rig airborne numerous times and there is no sign of stress or fatigue on the truss. I also drive my rig daily, no less than 60 miles on the freeway and around town and it handles great. Hopefully that addresses your concerns.

 

[IslanderOffRoad]

Sounds good, thanks.

I ask since I've looked at that truss as well and might be picking one up later this year.

 

[cal]

The mount should be as strong as the stock one.

What the TNT truss does not do for you is increase ring gear strength (or that is to say, decrease pinion deflection).

IMHO, thats pretty crucial to beefing up the 30. MattyJ is breaking ring gears faster than I change my oil.

 

[asp]

how can a truss decrease pinion deflection? do you mean axle-wrap type deflection or flex of the gear teeth from torque applied? ..not sure i followed.

 

[cal]

The pinion gear can (and will) push the ring gear away from it a bit, decreasing the contact patch and making it easier to break the teeth off of the ring gear.


Welding the truss to the third member makes it more rigid, and makes it more difficult for the ring gear to deflect. A good solid diff cover also helps, but I wouldnt run without both.


Look at the housing here, it might help to make sense.

 

[asp]

great answer. just what i was looking for. thanks. (i've read your thread and seen those pics before but i didn't realize that was a common mode of failure for a d30... or that that was the appropriate solution.)

 

[IslanderOffRoad]

The mount should be as strong as the stock one.

What the TNT truss does not do for you is increase ring gear strength (or that is to say, decrease pinion deflection).

IMHO, thats pretty crucial to beefing up the 30. MattyJ is breaking ring gears faster than I change my oil.

Thanks Cal.

 

[cal]

I don't know if its "the" appropriate solution, but I've been beating the snot out of my 30 for a little better than 3 years, while guys on similar builds are breaking them left and right.

It does seem to work.

 

[asp]

I don't know if its "the" appropriate solution, but I've been beating the snot out of my 30 for a little better than 3 years, while guys on similar builds are breaking them left and right.

It does seem to work.

that's what i was getting at haha.