Dana 28 questions/help with "Poorman's Posi"

[1RangerNut]

Hi, I'm gonna try the "Poorman's posi" but I need to know if

1) Can I just put the carrier back in they way it came out, and call it good?

2) Can I reuse the ring gear bolts, if not anyone know the size of them?

3) Should I replace the roll pin, if so anyone know what size it is?

Also, for the c-clip eliminator should I use the internal spring I bought from here or should I buy a different one and do an external one?


Thanks: Steve

 

[alwaysFlOoReD]

It's been awhile since I've done one.
IMO;
1] Put the carrier back in the way you found it, making sure that the same teeth are engaged ring to pinion. You can get vibrational noise if the teeth are put together in a different order. So clean the teeth and mark them. I didn't know about this when I did mine so ended up with harmonic noise in my 9". The d-28 didn't make noise tho, probably because of lower speeds when under load.
2] You don't need to remove the ring gear for side gear shim addition.
3] I don't remember a roll spring? [Like I said, it's been awhile] Personally I wouldn't worry about roll pin replacement as long as it hasn't lost its "spring" thru heat.
4] That you'll have to figure out on your own. I went with an exterior spring.

Richard

 

[UrbanRedneckKid]

External spring. Years ago when I decided to weld my front diff, I reassembled it with an internal eliminator spring. After repairing it a few times for various reasons, I went with an external spring.

Sent from my HTCONE using Tapatalk

 

[Captain Ledd]

1a) Yes

1b) R&P's are purposely made to have all the teeth mesh eachother at one point or another. Example, if you have a gearset whose teeth are easily divisible into one another (like 2:1), you get uneven wear patterns. The same teeth will contact the same opposing tooth, over and over again. But if you make one gear just 1 tooth off, each teeth will wear across ALL the teeth of each gear (eventually), yeilding a very even wear pattern. This is also why the np205 has a 1.96:1 gear, just a few teeth different. An actual 2:1 would have yielded odd wear patterns.

Another example, 20 tooth drive gear, 10 tooth driven gear = bad. Each tooth will contact only 2 other teeth throughout the lifetime of the set ; 21 tooth driven gear, 10 tooth drive gear = good. every tooth will eventually contact every other tooth in the gearset, yielding very even wear. Generally you have an even number and an odd number.

If you ended up with harmonic noise, it wasn't reassembled correctly.

2a) I believe so, they're not torque to yield so they should be good to use at least once or twice. Use red loctite.

2b) agreed. Not necessary for this procedure.

3a) As long as it isn't mangled and feels like it still holds itself in there, no sense of replacing it.

3b) Yup, some carriers have a special bolt, but my D35 had a little push/roll pin

4) I used an external one on mine. Since you have the internal style, try to run it and see if you like it or want something else. No sense in wasting money.

 

[1RangerNut]

It's been awhile since I've done one.
IMO;
1] Put the carrier back in the way you found it, making sure that the same teeth are engaged ring to pinion. You can get vibrational noise if the teeth are put together in a different order. So clean the teeth and mark them. I didn't know about this when I did mine so ended up with harmonic noise in my 9". The d-28 didn't make noise tho, probably because of lower speeds when under load.
2] You don't need to remove the ring gear for side gear shim addition.
3] I don't remember a roll spring? [Like I said, it's been awhile] Personally I wouldn't worry about roll pin replacement as long as it hasn't lost its "spring" thru heat.
4] That you'll have to figure out on your own. I went with an exterior spring.

Richard

I had to remove the ring gear to get the cross shaft out, the roll pin holds the cross shaft in, I ended up reusing everything, I'll have to remember to mark the teeth next time, also I only got one extra shim in & the spiders went right in but I can't get them to differ-ate I assume that's what I was after?

External spring. Years ago when I decided to weld my front diff, I reassembled it with an internal eliminator spring. After repairing it a few times for various reasons, I went with an external spring.

I think I'm just gonna run the internal for now cuz I couldn't find one locally and wanna get everything ready to swap in this weekend. Plus I don't think I'll have an issue since I don't have super soft coils?

 

[alwaysFlOoReD]

R&P's are purposely made to have all the teeth mesh eachother at one point or another. Example, if you have a gearset whose teeth are easily divisible into one another (like 2:1), you get uneven wear patterns. The same teeth will contact the same opposing tooth, over and over again. But if you make one gear just 1 tooth off, each teeth will wear across ALL the teeth of each gear (eventually), yeilding a very even wear pattern. This is also why the np205 has a 1.96:1 gear, just a few teeth different. An actual 2:1 would have yielded odd wear patterns.

Another example, 20 tooth drive gear, 10 tooth driven gear = bad. Each tooth will contact only 2 other teeth throughout the lifetime of the set ; 21 tooth driven gear, 10 tooth drive gear = good. every tooth will eventually contact every other tooth in the gearset, yielding very even wear. Generally you have an even number and an odd number.

If you ended up with harmonic noise, it wasn't reassembled correctly.

Thanks for the info, it's good to know.
And the pumpkins I've done may well have been reassembled wrong....I'm self-taught. TRS has been great for learning. Back when I first did this type of mod I was reading and doing out of hot rod magazines...when they were less than a buck. No internet, it wasn't even thought of. NO, I don't miss the good old days.

Richard

 

[Captain Ledd]

Mistakes happen, but I've been (somewhat) involved with some gear train design, one of the tid-bits I picked up. Just making sure to clear up any misinformation before it gets worse

 

[1RangerNut]

alwaysFLOoReD - should the spider gears be really hard to turn by hand?

Also, should I cut off the end of the shaft where the clip used to be, to help possibly keep the spring from binding in the slip joint? There's around half an inch of unused splines on the end.

 

[alwaysFlOoReD]

1] IIRC they are hard to turn.

2] I can't help you there, I have never done one.

Good luck,

Richard