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**DONOTDELETE** 09-28-1999 12:08 PM

Beefing up th400/Dana20 adapter
Hey guys: I swaped in a Dana 20 in place of my q-trac several months ago on my 77CJ7 and I've had problems with the 2 cr*ppy little "footings" that bolt the aluminum adapter to the skid plate(i.e. the transmission mount). I've busted these and rewelded them a couple of times, and now its starting to piss me off! Does anybody have any good, cheap fixes for this? I saw an article from back in the 80s where a company called T & J's in Aneheim, CA made a steel reinforcing bracket, but I can't find the company now. I guess its gone out of business. Any info or ideas? Thanks.

**DONOTDELETE** 09-28-1999 06:01 PM

Re: Beefing up th400/Dana20 adapter
1 Attachment(s)
sounds like ur a little lead foot there overtorquing that mount. :(
what did u do with the QT parts. m always looking for spares for mine :)

CJDave 09-28-1999 08:54 PM

Re: Beefing the torque arm
It isn't only the Dana t-cases that can crack the tranny adapter. When we tore our QT TH 400 down it was cracked as well. The cause seemed to be a poor fit-up which put all the strain on just a portion of the bracket. When we finally bolt this all back in, we will be adding a torque "outrigger" to the tranny/t-case adapter which will engage more bolts, more surface, and spread the load over a wider field. We had a tough time FINDING a TH 400 to QT adapter, and we want it to last this time. [img]/wwwthreads_images/icons/smile.gif[/img]


BigMan 09-28-1999 10:22 PM

Re: Beefing the torque arm
HAy dave... I have an adaptor for a q-track sitting in my garage if i havn't thrown it out yet.I was planing on trashing it but i think it's still there. It has the adaptor, bearing, and the output shaft fr the tranny.

My web page

CJDave 09-28-1999 11:05 PM

Re: Beefing the torque arm
ERK! DON'T trash that sucker! I need all the QT rare stuff I can get. Let's make a deal. I thought I was never gonna find one back in May when I was overhauling the tranny. Actually my transmision guy located one (at great expense) and I have worried ever since about what happens next time. I am using "relaxed concern" about QT parts in general, seeing as how they are basically obsolete.[img]/wwwthreads_images/icons/tongue.gif[/img]


**DONOTDELETE** 09-29-1999 12:01 PM

Re: Beefing the torque arm
Kenny & Dave:
I've still got q-trac parts too. In fact, I've got that same adapter Al does in a box somewhere. I also have an original LS gear, a full time chain or 2 (worn to an unknown degree), part time conversion gears, vacuum actuator, th400 output shaft, etc... I'm always interested in a trade. I'm a pack rat. Even when I don't need it anymore I still keep it. H*ll, I still have 72 Blazer parts and I haven't owned that in 2-3 years.
P.S. Kenny thanks for the photo, I always like checkin' out other rides.

**DONOTDELETE** 09-29-1999 03:15 PM

Re: Beefing the torque arm
Are you certain about adding a torque bar ?????
I have Ron Session's book on the th400 and there is no picture or reference (that i can find), that suggest to use a torque bar...
Not even on the high-output Chevelle's etc...

I reused the torque bar on my CJ7 Chevy 305 / gm th400 / "homemade" adapter / d300 swap, but i have later removed it. I think that the torque should be handled by the engine mounts, and the tranny mount should be used to hold the tranny against the skidplate (and be flexible enough, to absorb the torque movement).

I suspect that if you let the (alu) th400 case handle the torque, you could easily twist it to pieces ?????

I am *very* interested in any toughts about this subject......

<[email protected]>
Using self-discipline, see

**DONOTDELETE** 09-29-1999 04:46 PM

Re: Beefing the torque arm
Don't know if this applies, or not. I believe that Avance Adapters has addressed this adapter 'problem'. I see a note in their Buyers Guide that indicates 'This kit was made to replace the original Jeep adapter. The original adapters were very thin die cast metal, and our design offers a much heavier casting.' What I don't know is... does this comment apply to the Quadratrac, Dana 20, or both. And, knowing AA, I'm sure it will carry a significant price.
Best wishes.


CJDave 09-29-1999 04:52 PM

Re: Be aware of torque
[img]/wwwthreads_images/icons/wink.gif[/img] Ah, PerJ, good to hear from you. The truth is that in applications which do not have a transfer case, the torque is on the centerline of the TH400 and poses no problem since it cannot get a "lever" on the tranny. With an offset drive like a Quadra-Trac, there CAN be considerable "action" from torque, and some allowance must be made for it. Many of the late model transfer cases have the rear output on the centerline as well, and as long as rear drive is engaged, there is not much problem. [img]/wwwthreads_images/icons/smile.gif[/img] This is my engineer's analysis of the situation.


**DONOTDELETE** 09-29-1999 05:01 PM

Re: Beefing the torque arm
For whatever it's worth... I've been adding a 'torque-arm' to the last several conversions that I have done. I have more-or-less copied the general design of what is stock on a 80-86 CJ-7 with the 258 and a manual trans. I use flat stock, about 3/16 x 2, and the poly body-mounts for the doughnuts. I have purposely left it somewhat flexible. I see a picture in the AA Buyers Guide (p41) that indicates that AA is selling essentially the same thing that I am making. I've got perhaps a dozen people with this torque-arm, and no complaints, no broken T/C mounts, yet. I put it on one conversion that had a SM 465 and Dana 300. It had chatter without the torque-arm, and the chatter is gone, with the torque-arm.
Best wishes.


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