auto trans problem diagnosis
Thread Starter
|
Senior User
Joined: Dec 2004
Posts: 107
Likes: 0
auto trans problem diagnosis
My '64 has a 352 4V and 99% sure that it is a cruise-o-matic/ford-o-matic transmission. Both were taken out of a '66 Galaxie before I owned the truck. I am just learning about auto transmissions and I am a bit lost on how to diagnose the problems I am having.
If I am taking off from a start or slow roll and give it a decent amount of gas, there is a hard clunk. If I am accelerating slowly, it seems to do fine.
Sometimes from drive, it will clunk and then feel like it has slipped out of gear. I have to put it down into 2nd to get it to go back to gear.
If I am cruising and accelerating gradually, it seems to rev higher than what is needed/feel like it is slipping or in the middle of shifting for an extended time. I think this happens at around 35-40 MPH.
Is this transmission dying or are there things that can be adjusted to correct these problems? I know I should change the transmission fluid and filter, but I am wondering if the adjustments need to be made with the pan off. If these are signs that it is definitely dying, though, I don't want to waste $$ on fluid that I should be putting towards a rebuild instead.
thanks for your help!
Taylor
If I am taking off from a start or slow roll and give it a decent amount of gas, there is a hard clunk. If I am accelerating slowly, it seems to do fine.
Sometimes from drive, it will clunk and then feel like it has slipped out of gear. I have to put it down into 2nd to get it to go back to gear.
If I am cruising and accelerating gradually, it seems to rev higher than what is needed/feel like it is slipping or in the middle of shifting for an extended time. I think this happens at around 35-40 MPH.
Is this transmission dying or are there things that can be adjusted to correct these problems? I know I should change the transmission fluid and filter, but I am wondering if the adjustments need to be made with the pan off. If these are signs that it is definitely dying, though, I don't want to waste $$ on fluid that I should be putting towards a rebuild instead.
thanks for your help!
Taylor
Postmaster
Joined: Dec 1999
Posts: 2,813
Likes: 6
From: Connecticut
I would take the truck to a transmission shop and let them diag the truck. You could try a modulator valve to see if it's causing a late shift. The momentary shift into neutral may be a deeper problem. It may be just a band adjustment or could be worse. The valve body could be jummed up or a ball could be sticking. make sure they have a pan gasket ahead of time so you don;;t get stuck there. Let them drop it and see.
Barry
Barry
Thread Starter
|
Senior User
Joined: Dec 2004
Posts: 107
Likes: 0
Originally Posted by jowilker
Taylor, The first place I would look is at the U joints. Sounds like one or more may be spent.
John
John
--
I didn't realize this tranny had a vacuum connection. I definitely will be making sure that is intact. Is it supposed to be using manifold vacuum or some connection off of the carb?
After I address the u-joints, I am going to see how much a shop will charge for a checkup. But I am wondering why I shouldn't adjust and check the things Barry mentions myself.
Is there another name for the modulator valve? I can't find that one in the manual.
As far as adjusting the bands, the service manual mentions special tools, but is it safe just to use a torque wrench and some 1/4" spacer that I find/fabricate?
Same thing with the valve body, any reason not to pull it myself and at least inspect it, or even open it up and give it a good cleaning? It looks relatively simple and that it wouldn't need to be completely disassembled for me to make sure all the passages and were clear.
Thanks guys
Postmaster
Joined: Dec 1999
Posts: 2,813
Likes: 6
From: Connecticut
If you're going to drop the pan and valve body, be very careful and don't lose those little check ***** in the V/body. You'll need some gaskets for the valve body and possibly some for the separator plate if so equipped. The modulator valve also has a short metal rod that is in the passageway and when you remove the valve, it may drop out. This controls when it shifts. Make sure the vac connection hoses are good and don't leak. It gets it's vac from the intake.
Barry
Barry
Elder User
Joined: Oct 2004
Posts: 556
Likes: 0
From: Ridgeway, Virginia
Dont slop on a bunch of RTV silicone gasket maker when you button up the pan. Silicone has a way of really screwing up the valve body of a transmission. Many mechanics use no gasket sealer at all. Also pan bolts require very little torque. A lot will cause a leak. Just a couple of good tips...
Trending Topics
Thread Starter
|
Senior User
Joined: Dec 2004
Posts: 107
Likes: 0
I'm still wondering if anyone knows an acceptable alternative to using those Ford tools for the band adjustment.
---
Barry, I've been studying the Ford shop manuals for '64 F-series and '66 full-size (I believe the transmission is from the latter) and I don't see any gaskets in the explosions of the valve bodies, nor in the text of the disassembly/assembly procedure. Do you have a part number for the gaskets?
you guys are all a great help! thanks
---
Barry, I've been studying the Ford shop manuals for '64 F-series and '66 full-size (I believe the transmission is from the latter) and I don't see any gaskets in the explosions of the valve bodies, nor in the text of the disassembly/assembly procedure. Do you have a part number for the gaskets?
you guys are all a great help! thanks
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Postmaster
Joined: Dec 1999
Posts: 2,813
Likes: 6
From: Connecticut
OK, I did some digging and the Cruise-o-matic doesn't use those gaskets, unlike a later Ford tranny. I haven't seen the insides of one of these in a long time. I'm used to all the problems Ford has had with Taurus trannies, those I can remember!
Barry
Barry
Logistics Pro
Joined: Jun 2003
Posts: 3,928
Likes: 276
Is the Cruise-o-matic like a C6? One 2nd gear band? If it is like the C6, you go 10 ft. lbs. on the adjustment screw and back it off a turn and a half. The problem you're having sounds like the modulator valve is out of adjustment. Like the pressure is too low at an idle. There is a small screw in the port where the vacuum line goes on, if you screw it in, it raises the pressure as well as the shift points. Count the number of turns in that you adjust it to, so you can put it back if it doesn,t cure the problem. There are also different length modulator valve rods if the adjustment screw does not provide enough adjustment. I usually start out in 1-2 turn increments. Hope this helps.
Thread Starter
|
Senior User
Joined: Dec 2004
Posts: 107
Likes: 0
I changed the vacuum modulator yesterday, and added a bit of fluid (it was right on the "add" mark when it was warmed up). There does not seem to be a screw on the c-o-matic, but maybe I was looking in the wrong place. It seems like it is shifting much better now. I just got a tach so once I install it, I will be interested to see the speeds/rpm that it is actually shifting.
Plus, I now I understand that the first drive position on the "dual range" trans starts off in 2nd gear. I adjusted the shifter so that I can actually put it down in low too. I wonder if the shifter adjustment was to blame for the clunk, which is gone now. There is still barely enough space for park and low to be selected, so I will have to fiddle a bit more with the shifter to get it just right (this was originally a manual truck, and the shifter is kind of hacked into the floor).
I didn't drop the pan yet because I was kind of excited about these results. But I will definitely change the fluid soon, and adjust the bands. I don't know how similar it is to the C6, but there is a front and a rear band, and one of them is done the same as what insti8r describes-- I got a response on Network 54 about adjusting them.
Plus, I now I understand that the first drive position on the "dual range" trans starts off in 2nd gear. I adjusted the shifter so that I can actually put it down in low too. I wonder if the shifter adjustment was to blame for the clunk, which is gone now. There is still barely enough space for park and low to be selected, so I will have to fiddle a bit more with the shifter to get it just right (this was originally a manual truck, and the shifter is kind of hacked into the floor).
I didn't drop the pan yet because I was kind of excited about these results. But I will definitely change the fluid soon, and adjust the bands. I don't know how similar it is to the C6, but there is a front and a rear band, and one of them is done the same as what insti8r describes-- I got a response on Network 54 about adjusting them.
It is very easy without "special tools"
For the front band use a 1/4" spacer.
Adjust to 10"#'s, remove the spacer and TIGHTEN the screw one turn.
Rear band uses 10'#'s and back off 1 1/2 turns.
For the front band use a 1/4" spacer.
Adjust to 10"#'s, remove the spacer and TIGHTEN the screw one turn.
Rear band uses 10'#'s and back off 1 1/2 turns.
Thread
Thread Starter
Forum
Replies
Last Post
HillBillyBuddha
1961 - 1966 F-100 & Larger F-Series Trucks
2
Mar 5, 2014 12:19 PM
amwilliams55
1961 - 1966 F-100 & Larger F-Series Trucks
10
Mar 30, 2012 02:56 AM
taylor0987
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
9
Jun 3, 2005 05:56 AM