I started the truck and put it in drive and the car wouldn't move. I gave it gas and it wouldn't move. I drained the transfer case and it was a dark color and the plug had metal shavings all over it. The drain pan also had metal shavings in it. I'm in high school and I'm new to all of this. How much is a good quadratrac transfer case? I've heard of people doing something to make the chain in it last longer if you know what that is let me know.tgreese wrote: ↑Sun Sep 17, 2023 2:23 pm The Borg-Warner Quadratrac uses a unique output shaft in the transmission. The output shaft is the last part to come out of the case when you completely disassemble the transmission. You can purchase a conversion kit, but you will need to install the new transmission output shaft. There is no easy swap out there, Dana 20 or otherwise.
The Quadratrac also uses an offset rear axle that matches the offset rear output of the transfer case. There are conflicting reports about whether you need to change to a centered axle or not. (Sorry, disregard previous sentence. Not an issue for a pickup which uses a longer driveshaft).
Most owners decide that it's best to deal with the existing Quadratrac and service or repair than to swap. What issues do you have with the existing transfer case?
First post! Welcome from Boston.
Ok gotcha. But what about the metal shavings found in the fluid. My auto shop teacher seems to think it is metal shavings from warn out gears.letank wrote: ↑Sun Sep 17, 2023 9:45 pm Welcome from SF, bay area.
Dark color is/was the standard of the quadratrac (QT) it stinks also. How many miles, by now it may have been swapped to a part time kit, you will have locking hub on the front axel.
Otherwise not moving could be the vacuum control of the transmission. On the right side of the trans there is a vacuum modulator that is connected to the intake manifold vacuum. IIRC a quick test is to plug the vacuum tube or rubber line -to prevent a massive vacuum leak- at the source, at the engine side. Now your truck should move. Vacuum modulator go bad, and can be replaced.
Otherwise all QT knowledge is here:
https://jubileejeeps.org/quadratrac/
Novak has an adapter for TH400 to the Dana 300 that they say works with other NP transfer cases. Presume you're thinking something like the NP241C? Are there other passenger drop options?Stuka wrote: ↑Sun Sep 17, 2023 10:05 pm To swap in a Dana 20 you need the adapter that goes on the back of the TH400 for it. I believe Novak sells one. You also have to replace the output shaft on the transmission. Which does require pulling the trans, removing its internals, and putting the output shaft in for the D20.
If I was going to go through all that work, I would look into putting an NP style t-case in. Though I am unsure as to adapters for the TH400 for that. Though the TF727 that came in 80+ FSJs are setup that way from the start.
The 208 and 241 are what came to mind. Both are stronger than the D20, though cannot be twin sticked easily. The D300 can.tgreese wrote: ↑Mon Sep 18, 2023 9:48 amNovak has an adapter for TH400 to the Dana 300 that they say works with other NP transfer cases. Presume you're thinking something like the NP241C? Are there other passenger drop options?Stuka wrote: ↑Sun Sep 17, 2023 10:05 pm To swap in a Dana 20 you need the adapter that goes on the back of the TH400 for it. I believe Novak sells one. You also have to replace the output shaft on the transmission. Which does require pulling the trans, removing its internals, and putting the output shaft in for the D20.
If I was going to go through all that work, I would look into putting an NP style t-case in. Though I am unsure as to adapters for the TH400 for that. Though the TF727 that came in 80+ FSJs are setup that way from the start.
The low neutral high shifter was not in neutral. Do you recommend checking inside the transfer case? Or the vacuum shifter?tgreese wrote: ↑Mon Sep 18, 2023 1:58 am Not a good guess. Chain driven, no gears. Two big sprockets and a link belt between them. Read here.
https://jubileejeeps.org/quadratrac/index.htm
The chain wears out, but it slips and bangs when worn. Metal chips could come from the splines in the differential, or?
There is a vacuum shifter for "emergency drive" but I believe it only changes from normal full-time to locked part-time. Low range is a separate planetary transmission bolted to the back of the transfer case - see the article I linked above. It has a low-neutral-high shifter, which should be a flag shifter on the floor/tunnel, IIRC. If in neutral, the Jeep will not move.
Do you have locking hubs? If so, keep them locked in for now.
There is the complete 1977 TSM here, free to read and download. Suggest you do some reading and familiarize yourself with your Jeep. https://oljeep.com/edge_parts_man.html
You can use a selection of taps to figure out what fasteners you needAJW137 wrote: ↑Wed Jan 03, 2024 9:30 pm Thanks for your help everyone. I took the transfer case off and found a bunch of rubber sealant inside the transfer case that had gotten caught up. Everything is in good condition. New issue is, I'm in highschool and stuff in the shop gets moved around a lot and my bolts got taken. I'm missing at least one from every section. Can anybody tell me the sizing of the bolts so I can buy them at Home Depot or at a hardware store?