Toploader transmission woes (technical)

phartman

phartman

Senior Member
The toploader in my '34 is starting to act up. A little background....

The rear and ****** are open drive, out of a '48. The banjo rear has an upgraded axle and gear kit from Hot Rod Works. It also has the third "arm" from them that runs roughly parallel to the driveshaft to keep everything straight under the truck.

Somewhile back, the bracket holding the third arm to the crossmember broke, allowing the axle to twist under load, and to not always run straight and aligned. The truck let me know that the arm mount had broken when I hit a pothole. One of the rear shocks collapsed, the axle twisted, and it was immediately obvious that something was very wrong in the suspension. Luckily, it all occurred at low speed, and I actually made it home ok.

Got everything aligned and re-attached.

However, since then, the transmission has in high gear at 30-45 mph displayed a noise like there are marbles in the case. At first I thought it was wind noise, but it has gotten progressively louder. When it first started to occur, after a while it would go away as the transmission heated to operating temperature. Sometimes I would not hear it at all.

I changed the fluid, topped off the case, and again, the noise settled down.

But with the cold weather, the noise is back. Only in high gear, only at that range (or a little faster).

Bad bearing in the transmission? The binding up of the rear end alignment put a strain on the universal joints and prematurely wore them? Normal sounds for an old transmission?
Dunno.

Maybe you guys can give me some pointers before I go pulling the car down.

Thanks.
 
Two options, You have a bearing going bad or your repair does not have the driveshaft aligned correctly and there is a rotational load placed on the trans tailshaft at that speed. You can check for bearing issues by checking the color of the trans lube and looking for metal flakes or a graying color. To check for alignment issues take the vehicle for a test cruise, place your hand on the shift lever as you increase the speed to the noise point and see if you feel a vibration build up in the lever when the noise starts. If you feel a vibration at the noise point you will have to recheck the rearend locating brackets and pinion angles.
 
Just a thought ,,but could your driveshaft be a "hair" out of Phaze ??A little twist ,and the u-joints rattling a bit....You did say open driveline right....Maybe the rear end twist incident compounded your problem....Then again I've only had one cup of coffee this AM and I'm not following you.....Carl in SoCal
 
DICK SPADARO said:
Two options, You have a bearing going bad or your repair does not have the driveshaft aligned correctly and there is a rotational load placed on the trans tailshaft at that speed. You can check for bearing issues by checking the color of the trans lube and looking for metal flakes or a graying color. To check for alignment issues take the vehicle for a test cruise, place your hand on the shift lever as you increase the speed to the noise point and see if you feel a vibration build up in the lever when the noise starts. If you feel a vibration at the noise point you will have to recheck the rearend locating brackets and pinion angles.
Click to expand...

On the bearing going bad...I have a couple hundred miles on the lube in the transmission. Will that be enough for the color change to occur?

And second, how much of a loaded gun am I playing with? How will I know how far along the bearing failure/seizure might be? Will it give my any further warning before it goes, or could it fail at any time? The damage is already done...just wonder if it has a couple miles left in it or a couple hundred? Hard to tell, I suppose.

And my guess is the bearing is shot and not a continuing problem with mis- alignment. When the third member broke, that's what caused the mis-alignment in the first place and that is when the noise first appeared. I drove the truck a couple hundred miles, not realizing the bracket had broken. The misalignment of the rearend and the misalignment of the pinion angles put undue strain on the bearing. Now that the rear end is properly aligned (and I'm pretty sure that it is) the bearing is still shot.

In other words, just because the rear is now properly realigned and the pinion angles are where they should be, the damage is already done to the bearing(s) in the transmission. The proper alignment of the rear (unfortunately) won't repair the damaged internals on the transmission.

Just curious if I'm playing with fire when I drive the truck. Wondering how much life I've got left in the ******. It was pretty noisy yesterday.
 
I put a magnetic plug in the rear end and the trans, imagine my surprize as I drained the trans oil, and a (cluster) tooth came out... (This did save me from wrecking a whole gearset and case)
So, I put one mag plug high, and one in the drain... You can easily check the high one for particles... Ford Explorer uses a cool 3/8" pipe plug- I got a couple from the junk yard.
Karl
 
ford38V8.........You know,,your right..After my third cup of coffee I see that...
Note to Self: Never reply till after your third cup,and always look at "What the other Guy said before You".......Hey I'm new at this....Carl....!
 
reposted from another thread

A tip is to wave a magnet around in the fluid catch-pan (use a non-magnetic pan).

[If you have an old hard drive and you're not interested in the data. Get some small torx bits and open it up ($8 at Harbor Imports), harvest the magnet(s) inside. Incredibly powerful! Nothin' falls off my fridge. I find uses for them all the time.]

-VT/Jeff
 
You'll never guess what it turned out to be...the speedometer gear!!! I have a modern speedometer from Classic Instruments. When the speedometer gear gets a little dry, it howl and whines like a bearing is about to go out of the transmission.

Riddle solved.
 
glad you found the problem....and posted the solution/find.....always good to find out the end of the story....Mike
 
A thought on this, perhaps unwelcome: Open drive conversion means new suspension location system, exactly what broke here. Almost all hot rod locating systems for cross springs have geometric problems that add bending and twisting loads to parts not present with the torque tube as locator. Only a few with elaborate wishbone fabrication seem to locate without significant compromise.
I can understand going to open drive to get a 5 speed overdrive or to get stronger trans and rear...but with early Ford trans and rear in an early Ford, why have open drive adding complexity and potential failure points? As I said, I understand the need to re-engineer and perhaps accept compromised geometries to get different parts, but seems that here the stock tube would be the way to go.
The break you had could have been much worse at speed, adding in major rear steer, interference between tires and structure, and quite possibly locking up a brake by reaching the limit of the E-brake cables...
 
Bruce Lancaster said:
A thought on this, perhaps unwelcome: Open drive conversion means new suspension location system, exactly what broke here. Almost all hot rod locating systems for cross springs have geometric problems that add bending and twisting loads to parts not present with the torque tube as locator. Only a few with elaborate wishbone fabrication seem to locate without significant compromise.
I can understand going to open drive to get a 5 speed overdrive or to get stronger trans and rear...but with early Ford trans and rear in an early Ford, why have open drive adding complexity and potential failure points? As I said, I understand the need to re-engineer and perhaps accept compromised geometries to get different parts, but seems that here the stock tube would be the way to go.
The break you had could have been much worse at speed, adding in major rear steer, interference between tires and structure, and quite possibly locking up a brake by reaching the limit of the E-brake cables...
Click to expand...

Yup, my thoughts exactly. I kept the early rear. It's going back in.
 
I removed the spring and put coilover's on the rear of my 41 pickup to adjust the ride height. I retained the torque tube. After a couple of hundred miles one of my welds let go. So I reworked the buggy spring removing all but three leaves and reinstalled it. Ride height is OK and I feel safer. I ended up with a very expensive shock mount for the rear. I have a S10 T5 with the right gears, but the more I think about the work involved the better the 39 top-loader and torque tube look.. Even with a pan-hard bar and careful measuring I evidently didn't get it right.
 
This is where I chime in. Although we still sell the reman T5 trannies, I feel that the early Ford's with the torque tube chassis do the best when keeping the early 3 speed transmission in place. Change the trans gears and/or the rear end gears to get the highway driving experience that suits you best. You still get to "stir the stick" and do it like Grandpa did. You get the wonderful sound of those early gears too.....just my two cents.
 
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