Skeeter's Shakedown & Tranny Mounting Tech/Carnage

74_Chevota · Jul 5, 2008

Re: Clayton, OK 7/2008

Had the exact same thing happen to me, but fortunatly i was only 45 mins from the house. Sucks to take a rig on its first test ride and break the tcase off the back of the tranny. I braced mine on the back and was still nervous the second time out but it has not been an issue after months of beating on it.

under_psi · Jul 6, 2008

Re: Clayton, OK 7/2008

nolen...it was built on the bottom...nothing there to break it...

trans is out and on teh floor...i am shocked....jimmy the blade came over today and forced me to take it out...i am glad he did...i was laying down for a nap and he busted awn in....

we did make a startling revelation....aside from teh stripped front tranny pan bolt, we noticed that there was a HELICOIL in teh lower pass side attachment bolt on teh tail housing....hmm...also the other 2 intact bolts were suspect as well....seems to me that this 'fresh rebuild' was in need of a new case to begin with.....i dunno...heres a few pics of the carnage...

if you look closely, you can see the helicoil in the lower bolt hole on teh pass side of the tranny.....

it is getting dropped off first thing on monday for a new case....

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Juan_Hong_Loe · Jul 6, 2008

Re: Clayton, OK 7/2008

Louis. Sorry to hear about your issues. Once the you get all the bugs worked out I am sure you will be happy. Stay in there and keep it up. What happened top you is one of my main concerns when I started my build. Always worried about it after hearing Keith Bailey telling me the story of him having to swap trannies out while on the Ultimate Adventure. I know I'm not much help but I still love the buggy! :flipoff1:

74_Chevota · Jul 6, 2008

Re: Clayton, OK 7/2008

wow thats scary how much that is exactly like mine. Same side and same chunk broken off.

blacksheep10 · Jul 6, 2008

Re: Clayton, OK 7/2008

yup, I've had 2 350's like that. my 400's all broke on the bottom????

BamaTJ · Jul 6, 2008

Re: Clayton, OK 7/2008

Sucks Lou, but **** happens. At least you know what you can do to improve the mounts. I doubt the rear suspension bottoming out had much to do with that, probably a poor case and a little use.

GStone · Jul 7, 2008

Re: Clayton, OK 7/2008

That sux...just for the record mine is mounted the same way. Th350/adapter/Atlas hanging off the back...never broken and it's not a "K" case. I'd look at other factors before I just threw $$$$ at it.

wngrog · Jul 7, 2008

Re: Clayton, OK 7/2008

Mine has a mount on the adapter between the Atlas and the TH350, so basically the Atlas hangs off the adapter that is mounted to a crossmember that is on rubber bushings.

All the TC cars are like that. The first rear case brace they ever used was Kulas 3sp Stak because that bitch is so heavy.

BamaTJ · Jul 7, 2008

Re: Clayton, OK 7/2008

I am pretty sure mine is unsupported also, but I will check.

under_psi · Jul 7, 2008

Re: Clayton, OK 7/2008

GStone said:
That sux...just for the record mine is mounted the same way. Th350/adapter/Atlas hanging off the back...never broken and it's not a "K" case. I'd look at other factors before I just threw $$$$ at it.

what other factors should i look at...nothing was binding, bottoming out, that i know of...i have tons of travel in my drive shafts....

i am starting to think that the mounting bolts in the tailhousing were not in great shape with there being a helicoil in there and also the other threads did not look great either...however, that could very well be due to the fact that the chunk broke off and teh atlas was hanging only supported by 3 bolts....

DavidsCJ7 · Jul 7, 2008

Re: Clayton, OK 7/2008

I only have two trips on my Atlas, without rear support, but I definately think it is a good idea. That case is heavy. I dont think that is the cause of your failure though.

under_psi · Jul 7, 2008

Re: Clayton, OK 7/2008

:popcorn:

P · Jul 7, 2008

Re: Clayton, OK 7/2008

I vote Roark and never worry again..... I wouldnt install an Atlas without one personally, its just a neccasary piece and to simple/good insurance not to do one IMO.

BamaTJ · Jul 7, 2008

Re: Clayton, OK 7/2008

ROCK SKEETER said:
what other factors should i look at...nothing was binding, bottoming out, that i know of...i have tons of travel in my drive shafts....

i am starting to think that the mounting bolts in the tailhousing were not in great shape with there being a helicoil in there and also the other threads did not look great either...however, that could very well be due to the fact that the chunk broke off and teh atlas was hanging only supported by 3 bolts....

I think the bolts are a culprit for sure. Any chance the shafts are too long and and pushing against the case? That would really effect the Atlas though. I don't think a rear mount is a bad idea by any means, but I am not sure it is the main culprit.

vanguard · Jul 7, 2008

Re: Clayton, OK 7/2008

My dana 300 just hangs off the back (never a problem in a nearly 4 year old rig) but it really can't move much before it hits the skid plate. On top of that, dirt tends to pack between the t-case and skid plate providing a "zero movement" support.

I wonder if the guys that hang their atlas off the back also have a supportive skid plate that prevents it from moving?

wngrog · Jul 7, 2008

Re: Clayton, OK 7/2008

The only time I felt the need to support the atlas was with the 4 speed in the bash buggy because it was LONG. Like P said though....cant hurt or sure. Like the single v double sheer debate.

The course spline shafts have me thinking there is a chance it bound up. Of course, that is reaching.

Frank TJ · Jul 7, 2008

Re: Clayton, OK 7/2008

I just ordered a Roark support for my Atlas/231 Doubler setup. I got the Roark without the poly bushings, my tranny is hard mounted to the crossmember and the crossmember has poly at the frame mounts. Gonna fab up something to bolt the Roark to my crossmember.

GStone · Jul 7, 2008

Re: Clayton, OK 7/2008

ROCK SKEETER said:
what other factors should i look at...nothing was binding, bottoming out, that i know of...i have tons of travel in my drive shafts....

i am starting to think that the mounting bolts in the tailhousing were not in great shape with there being a helicoil in there and also the other threads did not look great either...however, that could very well be due to the fact that the chunk broke off and teh atlas was hanging only supported by 3 bolts....

I can only offer how mine is done. It solid mounts off the adapter to the cross member which is bolted to the main frame rails using poly bushings. The motor is mounted to the chassis by poly bushings also, there is enough clearence around the headers and the frame rails to slip maybe two playing cards and my exhaust has never hit the frame from motor torque. My point is, nothing is mounted on any kind of rubber or anything that has "give" in it. From seeing other rigs that have had a "tranny case breaking problem", I usually observed that either the tranny, motor or t-case had rubber mounts mixed with solid or all rubber mounts. I haven't seen one that had everything more or less soilid mounted break tranny cases. Now, I'm only speaking from person experience, I don't doubt there are exceptions.

After saying all this it's likely to break the next time out.

under_psi · Jul 7, 2008

Re: Clayton, OK 7/2008 (Tranny Carnage)

ok, here's the deal...

to give some knowledge of my set up..engine has the blue poly mounts on it tied to the frame....

atlas support ring has them also tying it to teh lower skid area....

now....i have taken the tranny to transgear here in town....carlton, their auto tranny guru says that i am probably right on thinking that it has something to do with the "OTHER" 3 bolts in the mounting surface...2 were severely stripped and the 3rd that was helicoiled....he said that they could have been loose and or already stripped and that was MOST likely the culprit....however, those bolts were all still pretty intact when the break was 1st noticed....and were only looking stripped when we got home after a long ride on the trailer.....who knows.....it is probably really a combination of all teh things that i think it is...under supported, bad bolt holes, and so on....

so, that being said, i am having the cases swapped...i am ordering a full manual reverse valve body with compression braking from TCI this week.....should have the tranny in next weekend.....

on another side note, fwiw, he also told me that i was wasting my time lookign for a "K" case...he said that the only 'difference' b/t the standard case and a 'K' case is that there is some extra material around where the dust shield bolts to the lower portion of the bellhousing...and that is only b/c in a factory application, that there are 2 tie rod like support arms that bolt to teh front of the aluminum dist shield and mount to the engine or mouts....for added rigidity....just an FYI for anyone who cares....