QT Sun gear/ shaft assembly

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Holland Waggy
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QT Sun gear/ shaft assembly

Post by Holland Waggy »

Just a thought, dealing with the worn splines on both shaft and sun gear; why not simply put the two pieces back together and weld them up? Or should there be a little endplay on the connection? And another possible fix; I got lucky and found another sungear on Ebay, so I want to put the shaft back in, but reversed. The PTO side is never to be used and the snap ring will still fit the groove. Its' possible I have to shorten the other end so it won't butt up with the tranny shaft but this could work right?
Gilbert Doggen

1978 Wagoneer, AMC360, TH400, Quadratrac, HEI Ignition, Headlight LED conversion,
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fulsizjeep
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Re: QT Sun gear/ shaft assembly

Post by fulsizjeep »

I have been fortunate enough to have spare low range units on hand when the 10 spline shaft and sun gear go bad in the low range so I have never torn one completely down before. I have heard of a few people who have done the swapping of ends on the shaft and as far as I remember, it fits either way without modification.
Flint Boardman
88 GW, 401/727/208, 5" lift, D44s/4.10s/locked up, 35s
https://jubileejeeps.org/quadratrac
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Holland Waggy
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Re: QT Sun gear/ shaft assembly

Post by Holland Waggy »

Now that's an answer I was hoping for. :D As soon as the sun gear arrives I put the shaft in backwards. Too bad that BJ's ran out of stock on the annual bearings but the old ones are still good to go. What kind of mileage are we looking at before the splines go bad again? There will be a new chain installed too, by the way.
Gilbert Doggen

1978 Wagoneer, AMC360, TH400, Quadratrac, HEI Ignition, Headlight LED conversion,
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fulsizjeep
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Re: QT Sun gear/ shaft assembly

Post by fulsizjeep »

Welcome to the forum by the way. :-bd

There are a few contributing factors on the 10 spline wear. If the tires are not all the same diameter, excessive wear in one or more driveshaft ujoints, excessive wear in a ring and pinion, low fluid level or wrong fluid in QT, high rpm shifts into Reverse or Drive, driving on hard surfaces in Edrive to name some. Typically, the T400 tailshaft takes the brunt of the wear. It is softer than the sun gear. If the worn tailshaft is ignored, the problem spreads to the sun gear and low range shafts.

Differential torque test can help diagnose the condition. It is in the TSM. If you don't have TSM, there is one here:
http://jubileejeeps.org/quadratrac/77jeep_qt_tsm.pdf
If you have not opened, cleaned and inspected the limited slip differential, you should. Good Luck with your project!
Flint Boardman
88 GW, 401/727/208, 5" lift, D44s/4.10s/locked up, 35s
https://jubileejeeps.org/quadratrac
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jsinajeep
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Re: QT Sun gear/ shaft assembly

Post by jsinajeep »

Yes the shaft can be swapped end to end. A friend in Arizona has done it.
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Re: QT Sun gear/ shaft assembly

Post by fulsizjeep »

jsinajeep wrote:Yes the shaft can be swapped end to end. A friend in Arizona has done it.
Yes, good. I thought Kevin told me that once before. :-bd
Flint Boardman
88 GW, 401/727/208, 5" lift, D44s/4.10s/locked up, 35s
https://jubileejeeps.org/quadratrac
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Holland Waggy
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Re: QT Sun gear/ shaft assembly

Post by Holland Waggy »

[quote="fulsizjeep"]Welcome to the forum by the way. :-bd

Thank you! Couldn't find an introduction thread, so here's my brief story;

I'm from the Netherlands and I wanted a Wagoneer ever since I was a kid. My neighbour across drove a Chief, and the impression of that massive grille coming down the street never left my mind. But it took almost 40 years to buy one. After a long search I finally found an unspoiled '78 Wagoneer, which was somewhat neglected. Rusty but worth all the effort and money im gonna have to put in. First started off with the driveline, so the QT is split open and the tranny was taken out for a rebuild. Steeringbox is rebuild so i should be leakfree for a couple of months now. Hoping to get everything back in by the end of next week, and in the meantime i'm fitting a new 2,5" exhaust. It's my goal to use the Wagoneer as my daily driver, no matter how it looks. As long as it drives well, i'm happy. :mrgreen:

When i figure out how, i'll post some pics.

Gilbert
Gilbert Doggen

1978 Wagoneer, AMC360, TH400, Quadratrac, HEI Ignition, Headlight LED conversion,
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Holland Waggy
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Re: QT Sun gear/ shaft assembly

Post by Holland Waggy »

The rebuild of the QT is allmost done. I got lucky and received the stub shaft together with a decent sun gear and I also got an original Morse chain which someone probeably had lying around for some years. Now I'm running into this problem; when installing the pinion cage on the drive sprocket it's difficult to get the snap ring on the sprocket. But if i try, the pinion cage is rubbing against the transfer case. Is this normal? I can see some wear and minor grooves, but this seems an odd assembly. Wish i made some more pictures dissambling the unit... TSM has no clear answer to this, who can help out?...
Gilbert Doggen

1978 Wagoneer, AMC360, TH400, Quadratrac, HEI Ignition, Headlight LED conversion,
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fulsizjeep
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Re: QT Sun gear/ shaft assembly

Post by fulsizjeep »

That was quick. :-bd Nice score on the Morse chain! I am having trouble picturing the snap ring you speak of. Can you provide picture(s) of this?
Flint Boardman
88 GW, 401/727/208, 5" lift, D44s/4.10s/locked up, 35s
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Re: QT Sun gear/ shaft assembly

Post by Holland Waggy »

Thanks Flint,

I wish i bought both of them chains! He had two actually, but i wasn't sure if it was the real thing before i got my hands on it. Here's are some pictures i've made this morning;

this is the snap ring i spoke of;

Image

Image


When i push back the pinion cage far enough to get the snap ring in the groove on the drive sprocket, the cage is hitting the transfer case.

Image

Image

The TSM says it has to go there

Image

What am I doing wrong, or perhaps what am I thinking I'm doing wrong?

Grtz,

Gilbert
Gilbert Doggen

1978 Wagoneer, AMC360, TH400, Quadratrac, HEI Ignition, Headlight LED conversion,
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fulsizjeep
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Re: QT Sun gear/ shaft assembly

Post by fulsizjeep »

Thanks for the pictures. Gotcha, I understand what you mean now.

I wonder if you have the thrust washer as seen on right side of the following image.
Image
Disregard the left side, that one has a part time kit.
Flint Boardman
88 GW, 401/727/208, 5" lift, D44s/4.10s/locked up, 35s
https://jubileejeeps.org/quadratrac

78 Arizona Chief
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Re: QT Sun gear/ shaft assembly

Post by 78 Arizona Chief »

Good morning. In reference to the snap ring, the internal drive sprocket has a bit of thrust play. You need to pull the sprocket out while pushing the pinion cage in, then the snap ring will engage. Just checking but you did put the fiber (or new ones are plastic) thrust washer between the rear half of the case and the inner sprocket didn't you?

Also, yes, I have been able to remove the stub shaft and reverse it in the sun gear. Eliminate all spline swap. Have one that has a little over 30k miles on it and still tight. Of course it is only tight on a smaller section of the teeth so I can't imagine it lasting all that long.
Kevin
1978 Cherokee Chief: Parents bought new. 360/TH400/NOS Quadratrac, 44's/ARB's/4.10's, SOA, Shackle Flip, Alcan Springs, FOX 2.0's, 35" BFG KM2s, custom bumpers, 324,000 miles and counting...

78 Arizona Chief
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Re: QT Sun gear/ shaft assembly

Post by 78 Arizona Chief »

Quadratracs are kinda like a guilty pleasure drug. Been a while since I had my fix. Gonna need to take another hit soon!
Kevin
1978 Cherokee Chief: Parents bought new. 360/TH400/NOS Quadratrac, 44's/ARB's/4.10's, SOA, Shackle Flip, Alcan Springs, FOX 2.0's, 35" BFG KM2s, custom bumpers, 324,000 miles and counting...
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Re: QT Sun gear/ shaft assembly

Post by fulsizjeep »

:funnypost: Take a hit! :lol:

Thanks for joining in on this one Kevin!
Flint Boardman
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will e
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Re: QT Sun gear/ shaft assembly

Post by will e »

Welcome Gilbert! What part of the Netherlands are you located? I visit Nijmegen and Eindhoven at least once each year.
81 Waggy 'WILL E' Retired
82 Cherokee WT - SOA/SF/high steer/Alcan springs/agr box/Borgeson steering shaft/AMC 401/performer/holley TA/HEI/BeCool/727/ALTAS (2.0/2.72/5.44)/D60 Snofighter(Yukon Zip,hubs,stubs,4.56)/14 Bolt (FF,BF shave, Discs, ARB,Artec Truss)/MTR 37X12.5/Corbeau XRS Baja & 5 point retractable harness/Hella Aux lights/tuffy console/killer32 sliders/Evil Twin bumpers, rack and roll cage/WARN 8000/TT Fabworks steering brace/dual batts/custom TC skid plate/ARB fridge
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Holland Waggy
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Re: QT Sun gear/ shaft assembly

Post by Holland Waggy »

will e wrote:Welcome Gilbert! What part of the Netherlands are you located? I visit Nijmegen and Eindhoven at least once each year.
Hi Will, I'm in Bergen op Zoom, which is approximately 70 miles east from Eindhoven. My brother lives in Eindhoven. Stop by over here, once you arrive in Holland the next time!

Thank you all for your reactions; Yes, the fiber thrust washer is intalled correctly and my not so problem is solved now; Because of the endplay on the drivesprocket and the fact the case is lying on it's side, the shear weight of the sprocket pulls it down. That's off course why the cage is hitting the case and the snap ring doesn't go on very well. How did I missed that... Tilting it and pushing the sprocket forward will solve that issue. It still feels strange that the cage can run into the case because of the end play but probably it will be kept in place by the drive chain. For the reversal of the shaft; it didn't need to do that, because i got a decent shaft with the sun gear. Kind of a surprise!

Got a call this afternoon that my TH400's rebuild is ready and i can pick it up monday. So if all goes well, the drivetrain will be completely reinstalled by the end of the week. I will fit a new exhaust as well wile it's on the ramp.

I'll keep you posted and thanx again for all the help!

Grtz,

Gilbert
Gilbert Doggen

1978 Wagoneer, AMC360, TH400, Quadratrac, HEI Ignition, Headlight LED conversion,
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Re: QT Sun gear/ shaft assembly

Post by fulsizjeep »

Good news! On a side note, I have opened up 3 or 4 QTs without that thrust washer and the case tends to get ground on by the sprocket and not so on the other side where the planetary cage is. Hope to see you are driving it soon! :-bd
Flint Boardman
88 GW, 401/727/208, 5" lift, D44s/4.10s/locked up, 35s
https://jubileejeeps.org/quadratrac
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Holland Waggy
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Re: QT Sun gear/ shaft assembly

Post by Holland Waggy »

The QT is ready and my tranny is lying in the boot of my car, ready to be installed on thursday. Good thing I had it rebuild cause the guy who did the job found some broken parts inside. Solenoid looked burned and one accumulator was broken in half. Also the torque converter has been redone and there's a new vacuum modulator installed. So this should make one heck of a difference! I do have one question about re-installing the QT; Can it be put back with the reducer installed or do it put it on later? I allready took it off before I removed the QT, but it looked like if the fuel tank would be in the way when you pull the QT backwards over the tranny shaft. But i'm not shure about that..
Gilbert Doggen

1978 Wagoneer, AMC360, TH400, Quadratrac, HEI Ignition, Headlight LED conversion,
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Re: QT Sun gear/ shaft assembly

Post by fulsizjeep »

Excellent. I have removed and installed them with and without the low range (reducer) mounted. It is heavier and much more awkward to put back in with it mounted. As I got older and a little smarter, I started taking it off first and installing it last. :)

Install the T400/QT adapter to the tranny before you put it in the Jeep. Remember not to rest the QT on the T400 tail shaft while installing it. That will crush the 2 front seals. I use two 3-4" threaded rods through one side of the T400/QT adapter that is threaded to hold the QT while getting it into position.
Flint Boardman
88 GW, 401/727/208, 5" lift, D44s/4.10s/locked up, 35s
https://jubileejeeps.org/quadratrac
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Holland Waggy
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Re: QT Sun gear/ shaft assembly

Post by Holland Waggy »

Ok thanks, I'l put it back in when the QT is fitted. I'm not that old, but just smart enough! ;-) Good one on those seals, I shall try to get some threads that will fit in. Makes life a lot easier I think..

To the hardware store it is!
Gilbert Doggen

1978 Wagoneer, AMC360, TH400, Quadratrac, HEI Ignition, Headlight LED conversion,
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