Transmission in 1972 Chieftain Not Shifting

[khantroll]

Hello! As some of you may know, I recently purchased a 1972 Winnebago Chieftain 24CL. Now, I have run into my first unexpected problem: the transmission is not shifting. In fact, it seems to be stuck in a forward gear. If I put the gear selector in park, it will creep forward; if the I place it in reverse, it either creeps forward or acts as though it is in neutral or park.

I have never seen a vehicle behave this way, but then again I know nothing about these transmissions. I thought perhaps it was a linkage issue, but the linkage seems to be working properly.

Has anyone ever heard of something like this, and does anyone have any ideas on how to fix it or at least narrow it down?

Thanks in advance,

Jeff

[UK-Winnie]

If the linkage is OK but it still creeps forward in Park then the parking pawl may be broken.

Apart from that it sounds like low fluid, burned out bands/clutches or an internal linkage fault.

What does the fluid look/smell like?

[khantroll]

The fluid smells like transmission fluid, and is a pretty red color. That is why I am scratching my head a little, because it was working, and the fluid doesn't smell burned which I figured would happen with a severe failure. I am not exaggerating when I say I parked it after driving it, and then the very next day I went to start it and it did not shift.

Could it be a stuck valve body?

[legomybago]

Have you had a helper go through the gears in the cab while you lay underneath and watch the throw of the linkage? You could unhook the cable on the tranny end, then select the gears yourself? See what it does....Sounds like something came loose to me. perhaps the linkage arm that selects the gears/internals of the tranny? Is the cable tight on both ends? Some ideas....

[Stripe]

I was thinking same thing, maybe a loose cable... i??

[khantroll]

I'm sorry for the long delay in replying, but my schedule got re-jiggered and I had to work onsite in another state for a couple of days. I just got out from under it, and the shift linkage seems to be operating correctly. I would have dropped the pan and tried to get a better look at the internals, but I have to go back out of town tomorrow and I unfortunately didn't have the time.

I will probably drop the pan later, but I think something must have broken inside. 

I guess I'll have to rejigger my repair schedule to include a tranny swap

[khantroll]

Hi all! I was working on the winnebago, and I had a question, and I also thought I'd give an update. I have been steadily  tinkering with Wiley the Winnebago as my schedule would allow (this contract has been extended twice, sent me out of town, and just generally been a PITA).  Further, my mother has had some medical issues (and the attending financial issues), so money that would have gone into this project has been diverted.

But, even with the above, I have:

Replaced the propane regulator and attending hoses
Done a full tune up (including new coil)
Cleaned the carburetor
Tinkered with the brake (bled them, rebuilt a wheel cylinder).
Patched the roof

Depending on the end of the month finances, I hope to completely replace her roof at the end of this month. But, at any rate, I have finally had time to get back to this transmission issue.

I dropped the pan, and there was not any metal at all in the bottom; in fact, everything that I could see looked wonderful. But the fluid seriously has me concerned. The fluid that came out was hard to describe: if you looked at it in small amounts in the light, it looked a dark red, but in thicker concentrations it looked black and even green. If it didn't smell like old, warn out tranny fluid I'd assume that some had dumped engine oil in the transmission.


I did some further research before dropping the pan, and the only things I could find where a 727 acted this way (stuck in drive, essentially), were attributed to old and warn fluid and a clogged filter. The service book I have for vintage trucks (I will provide the name when I get home, it escapes me atm) suggested three things:

1.) shift linkage (checked
2.)Clogged, stuck valve body (hoping this takes care of that)
3.) Broken or unhooked manual linkage arm, which is a rod on the backside of the valve body. What I can see of it with the pan dropped looks okay.

So, I'm about to put the pan back on and fill it up, even though I will probably wait until later in the week to test it (I need a new battery). any rate, I was cleaning up the pan, and that brought me to my question. My pan has these hollow tubes that pass through the pan, and I figure they are for cooling.

Is this some kind of after market thing, or do others have them? Here are pictures:

[Oz]

Aftermarket.  No cooling tubes in OEM pan.  I've seen these available from JEGS & Summit.

[khantroll]

I figured so, I've just never seen an air based cooler like this before. Most after market tranny coolers out there today are remote fluid coolers, and the air coolers are finned arrangements with fans.

Hmm.. that means that the overheating on grades that this thing does is not a symptom of old fluid or similar, but has been an ongoing issue; at least enough at least that this thing was added

[Oz]

Kind of a dumb question, but do you have the service manual?

If not, check this out, it's an invaluable tool for an incredibly low price, with a priceless bonus!
http://www.classicwinnebagos.com/forum/index.php?action=store;sa=view;id=144

[khantroll]

Hi Oz, yep, I have that manual, and the other two. They are great resources, especially for parts and diagrams on the odd models like my m375. The troubleshooting and rebuild info in what I call "The Big Green Book" seems more complete (to me, could just be that it has more pictures). This manual is a service manual for trucks ranging from 61-71, including medium  duty vehicles. The dodge brake and dodge transmission sections are quite helpful for Winnebagos.

I will post the name and publisher info when I get home. I meant to last night, but after getting rancid transmission fluid out of my hair, sleep was on the agenda.

[legomybago]

Look for a drain on your torque converter too. Some do, some dont.

[khantroll]

Hi Lego! Mine is the one that doesn't have the drain. Is it worth pulling the transmission to empty it?

[Froggy1936]

KT  No, Its not worth it (unless you need a new frt trans seal also) The convertor will drain approx 60% with it mounted to the flywheel , Out and turned snoot down it still will not drain completely due to shape . It is easier to drop the pan twice (driveing the veh in between )  getting about 95% of all the old fluid out .Though its not really necc unless you have major metal contamination , Then you are most likely overhauling anyway . If you do replace the frt seal also replace the frt pump bushing ! Frank