budget 258 rebuild

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I checked the yolks when I was initially working on it, and they seem to be alright. The reason I suspect the viscous coupling is 1. I already know its shot, it let the silicone out a long time ago, and 2. it only vibrates in reverse under load in 2wd. It works fine, no noise or complaining in 4wd. Frankly, as long as its not a transmission problem, and it doesnt impact operation, I am happy enough to write it off as an 80s turd quirk.
I am already keeping an eye out for a new transfer case

Edited by TheBirdman - Dec/19/2017 at 12:39am

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TheBirdman Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Oct/25/2017 Location: Sioux Falls, SD Status: Offline Points: 76	Post Options Post Reply Quote TheBirdman Report Post Thanks(0) Quote Reply Topic: budget 258 rebuild Posted: Dec/19/2017 at 12:36am
	I checked the yolks when I was initially working on it, and they seem to be alright. The reason I suspect the viscous coupling is 1. I already know its shot, it let the silicone out a long time ago, and 2. it only vibrates in reverse under load in 2wd. It works fine, no noise or complaining in 4wd. Frankly, as long as its not a transmission problem, and it doesnt impact operation, I am happy enough to write it off as an 80s turd quirk. I am already keeping an eye out for a new transfer case Edited by TheBirdman - Dec/19/2017 at 12:39am
	1983 Eagle Wagon 4.0 from 93 cherokee AW4, NP242, and EFI from 99 cherokee

billd Members Profile Send Private Message Find Members Posts Add to Buddy List Moderator Group Forum Administrator Joined: Jun/27/2007 Location: Iowa Status: Offline Points: 30894	Post Options Post Reply Quote billd Report Post Thanks(0) Quote Reply Posted: Dec/18/2017 at 11:20pm
	Vibrations related to a spinning part will do it any time that part spins - converter would vibrate depending on engine speed and never change based on vehicle direction since the engine is what is spinning it. Fluid, that sort of thing, can't cause a vibration. Vibrations are caused when a spinning part isn't balanced or isn't spinning true. A spinning part that is wobbling due to a loose bearing, for example - but even at that, as long as it's balanced it shouldn't vibrate unless that part is really seriously out of whack. Anything in the transfer case that's causing a vibration would mean a totally worn part - something that is moving around instead of just turning. Check the driveshafts, yokes, etc. if one has a loose bearing, such as a shot pinion bearing or the output shaft bearings of the t-case are shot............. could vibrate. Shifting is handling by a balance between governor pressure and throttle pressure. It's a tug-o-war between the two. As the vehicle moves faster it spins a governor in the transmission - weights move out against spring pressure raising governor pressure. As the gov pressure rises it wants to push the valves involved in shifting. Throttle pressure works against that. More throttle means you move the linkage and raise throttle pressure which pushes back against governor pressures and delays the shifts. Low throttle means lower throttle pressure and governor pressure overcomes it more easily and the transmission shifts. So as you push the gas, you raise throttle pressure and that pushes back against governor pressure preventing the shift spools/valves from moving. Let up on the gas and you let the throttle pressure drop and governor pressure overcomes throttle pressure sooner allowing upshifts sooner - but also against lower pressures so the shifts aren't as hard or harsh. That's the over-simplified version of what goes on. I have all of the charts of the time, the pressures as far as what they should be under what conditions and so on as I used to rebuild automatic transmissions as part of my job (and we did a whole semester on transmissions and differentials, etc. in college) However, shift kits mean you throw all that out the window - a pro will do more than just toss a kit in and say there ya go........... I've seen parts literally SNAPPED OFF the case from messed up valve bodies and folks not getting some little thing right - even a piece of lint. I saw one that broke the case, and another that snapped the band solenoid clean off the case. The pressures were so high and the shifting was so out of time it wasn't fully out of one gear before the next applied and going down the road it tried to do two at once - the car jerked and things snapped. We had a test stand we could mount any automatic onto and literally run it as if in a car - testing shift points, pressures and so on. It had a Ford four cylinder engine to run it and the output shaft connected to a heavy counter-weight to simulate the car being on the road. Worked slick - that way you could test things out before it ever was released to a customer or put in a car.
	http://theamcpages.com http://antique-engines.com

TheBirdman Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Oct/25/2017 Location: Sioux Falls, SD Status: Offline Points: 76	Post Options Post Reply Quote TheBirdman Report Post Thanks(0) Quote Reply Posted: Dec/18/2017 at 10:41pm
	Ha ha, silly me The vibration isnt even the transmission at all, its the transfer case. It works fine in 4wd, and the reason I thought it went away for a week it that I was driving in 4wd for a week. Since I already knew my viscous coupling was shot, this news is like christmas.
	1983 Eagle Wagon 4.0 from 93 cherokee AW4, NP242, and EFI from 99 cherokee

TheBirdman Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Oct/25/2017 Location: Sioux Falls, SD Status: Offline Points: 76	Post Options Post Reply Quote TheBirdman Report Post Thanks(0) Quote Reply Posted: Dec/17/2017 at 4:32pm
	What I did is I put two marks on the linkage, one on the rod, and one on the wire. I measured the distance between them when set at WOT, and the distance when set at idle, then took half the difference and set it right inbetween. The shifts are back to where they should be, but my reverse vibration has returned. Seeing as it hasnt gone away after setting the linkage back to how it was means that the reverse vibration is not a product of a wrong TV setting. Basically, when I give it any more than a little gas in reverse, it will vibrate. I used to think it was a shudder, but after looking up a few transmission shudders on youtube, this vibration isnt nearly as violent and doesnt actually affect the speed of the car, it just vibrates. I checked and put it in reverse, then gave it some throttle while holding the brake, and it does vibrate when stationary too. Has anybody else heard of something like this? I am hesitant to blame the torque converter, as it would seem like it would happen in the forward gears too if that were the case, and all 3 forward gears work fine. I read in this page: https://www.allpar.com/mopar/transmissions/torqueflite-fixes.html that there is a high pressure relief ball that is known to buzz in reverse, but it also says a transgo kit would correct that. I am puzzled as to why it went away for a week or so after installing the shift kit, and now its back. Maybe the crappy fluid that was left in the cooler lines and torque converter when I drained the transmission is the culprit. I may try draining out some fluid from the cooler lines while its running, then refilling it with some good atf+4, instead of the cheapo oreilley atf I put in it before. Edited by TheBirdman - Dec/17/2017 at 4:35pm
	1983 Eagle Wagon 4.0 from 93 cherokee AW4, NP242, and EFI from 99 cherokee

TheBirdman Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Oct/25/2017 Location: Sioux Falls, SD Status: Offline Points: 76	Post Options Post Reply Quote TheBirdman Report Post Thanks(0) Quote Reply Posted: Dec/17/2017 at 2:11pm
	I had similar thoughts, but while i was trying to figure out the reverse shudder. I still dont knkw if reverse pressure goes off of the tv or if it gets constant pressure. I seem to remember reading something about the shift kit supplying extra reverse pressure, but i cant remember
	1983 Eagle Wagon 4.0 from 93 cherokee AW4, NP242, and EFI from 99 cherokee

232jav3sp Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jan/09/2013 Location: Texas Status: Offline Points: 2451	Post Options Post Reply Quote 232jav3sp Report Post Thanks(0) Quote Reply Posted: Dec/17/2017 at 11:49am
	Hmm... Well, I would try adjusting it so there is roughly a 3/16 gap between the cam and the piston. I wasn't able to find any info about the stopper's adjustment in the service manual at work, and that is why I called my trans guy to make sure that gap is supposed to be there. You would think that the cam is always supposed to be in contact with the piston and that they move together through the throttle range. But, after I've had some time to think about it, at idle and at tip in (just off idle) you really don't need added line pressure to just roll/coast in first gear. That's why the gap is there. It's not until you are accelerating and the trans is needing to change gears that the piston needs depressing.

TheBirdman Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Oct/25/2017 Location: Sioux Falls, SD Status: Offline Points: 76	Post Options Post Reply Quote TheBirdman Report Post Thanks(0) Quote Reply Posted: Dec/17/2017 at 9:31am
	Correct. I didnt know how to adjust it, so i called transgo support, and he told me to set it to 900 thou from the bracket, which took the gap out of the cam and added a little pressure.
	1983 Eagle Wagon 4.0 from 93 cherokee AW4, NP242, and EFI from 99 cherokee

232jav3sp Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jan/09/2013 Location: Texas Status: Offline Points: 2451	Post Options Post Reply Quote 232jav3sp Report Post Thanks(0) Quote Reply Posted: Dec/17/2017 at 9:28am
	It happens, pal. I'm not offended. I reread my last post and it didn't flow like I thought it did after last night's proof read. Lol. So, you adjusted the stopper screw so there was no gap between the cam and the piston?

TheBirdman Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Oct/25/2017 Location: Sioux Falls, SD Status: Offline Points: 76	Post Options Post Reply Quote TheBirdman Report Post Thanks(0) Quote Reply Posted: Dec/17/2017 at 9:23am
	Ah, sorry for the misunderstanding. When i put the valvebody back together from the shift kit install, i adjusted the screw so that there was so slack in it.
	1983 Eagle Wagon 4.0 from 93 cherokee AW4, NP242, and EFI from 99 cherokee

232jav3sp Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jan/09/2013 Location: Texas Status: Offline Points: 2451	Post Options Post Reply Quote 232jav3sp Report Post Thanks(0) Quote Reply Posted: Dec/17/2017 at 9:15am
	I believe you are misunderstanding what I have said. I'm not saying to have the TV cam slightly depressing, or even touching the piston. You don't want that; as you will have too high of line pressure, which creates the late shifts you described a post or two ago. There should be a gap between the cam and the piston when at idle. The cam is supposed to be against it's stop at idle and fully depress the piston at WOT. This is what I had thought I had clearly explained in my last post. Being able to see the TV cam, it's stop, and the piston may very well greatly help you to get it adjusted properly. If I'm not mistaken, there was a good 3/16-1/4" gap on the 46RE I adjusted. Called my trans guy back east to confirm what I was seeing was correct and he gave my the green light. Man has been doing this for thirty years and he's built many a Chrysler trans for me, so I trust he is correct.