Rebuilt Trans + Torque Tube, Groaning / Grinding On Deceleration

[left.covst]

Hello all!

Long time reader, first time poster.

Recently performed some sealing and light rebuilding on my '40 side-loader and torque tube combination under my '34 pickup. A failed throwout bearing had me in there, so I took the time to fix all leaks and install an oil baffle from Bruce for the rear end to end my rear end > torque tube > transmission leak.

I replaced - input shaft bearing, snap rings, throwout bearing, countershaft thrush washers, a bent oil slinger, and all seals. Thoroughly cleaned and re-assembled the transmission. Also replaced the front driveshaft seal and bearing race, cleaned and greased the original torque tube roller bearing.

I also cleaned the torque tube and found my center bearing in visibly good shape, and re-greased it.

At the rear end I found the double nut for the pinion loose, and cranked it down a bit, without much thought to the pre-load / tightness at the time. Installed the baffle at the rear of the torque tube, and re-assembled everything.

Greased the u-joint well and thoroughly with cornhead grease until it made it to the front of the speedo gear.

All went well, and it all went together nicely and sealed up tight. Shifting is perfect, and it was nice and quiet for about 20 miles.

Unfortunately it has since developed a loud groaning / howling noise when in gear and coasting (engine braking). This continues until about 15-10 mph and then quiets down.

Pressing in the clutch will stop the noise, as well as pushing the trans out of gear.

It occurs only when coasting, and disappears as soon as the throttle is applied enough to positively drive the gears + rear end.

In reverse gear the groaning / grinding noise is not present.

I have three suspicious and would appreciate any input before I tear back into things:

1. Pinion nut was too tight - Causing bearing noise due to the pinion bearing.

2. Roller bearing in the torque tube inadequately lubed - Cornhead grease flowed to the top of the speedo gear opening, but I did not continue to pump it into the roller bearing area. Though I did pre-grease that section.

3. The original transmission roller bearing (either on the counter shaft or input-mainshaft ones) which were cleaned, greased, and reinstalled (though perhaps not in their original positions) could have failed or are failing OR the replacement thrust bearings on the countershaft are making noise.

Appreciate anyone's thoughts!

[Ken/Alabama]

Sounds like too much backlash in the rear end.

[petehoovie]

Very Nice '34 Pickup...

[deuce_roadster]

By tightening the 2 nuts on the pinion you moved where the gears touch each other and most likely increased the backlash. I would guess the worn area on the pinion is meshing with a differently worn area of the ring gear. Probably should redo the whole thing with new gears and bearings and set it up correctly.
Nice truck.

[ford38v8]

What Deuce Roadster said, and if you've driven it like that for a while more than just around the block, you'll find shavings in the differential oil. By the way, that double nut... Didn't it have a locking fold-over washer?

[left.covst]

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Thank you all for the feedback! I think Deuce likely nailed it.

Alan - Definitely drove it more than needed to toast it if there was a mesh issue. I'll try to do some additional diag with it running up on stands to isolate the noise and ensure it's in the rear end and not transmission area. I'll probably drop the diff oil as a final check before I split the assembly again, hopefully i'll find a smoking gun.

Might be an excuse to put a quick change center section in.

The pair of nuts did have a locking fold over tab, locking the two nuts together and neither of them tight, haha.

Alan - I see you're in the Bay as well, San Jose here!

[ford38v8]

Left Covst, yes, I'm here in Livermore, not really that far Left. As your locking tabs were folded over, but the nuts were loose, the likely cause of failure would have to be that a new pinion bearing had been installed short of full seating. That bearing is a press fit, and to do it without a press would require freezing the bearing and heating the banjo. Without a visual confirmation of full seating possible, this method and the use of a BFH is the only way I would do it. It takes a while to get a jig set up, but then just one big whap with the hammer does the job. I could have taken it down to Campbell, but was stubborn about doing it all at home. Bill is good about allowing V8ers to use his press.

[left.covst]

Nice Alan! I have a friend in the Walnut Creek area, I'm sure we'll cross paths before long.

Understood on the install. I am leaning towards a quick change rear end center section (Winters SR3620) as the ring and pinion do seem toast. Luckily I have a friend with a press for the carrier bearings should I go that route.

I got the car up on the stands and ran it today - Two videos attached of the truck running and the oil out of the rear end, I think it's safe to say I found the source of the noise.

https://share.icloud.com/photos/052B...wFkURN97d_HnPg

https://share.icloud.com/photos/04eO...23H6sLy2YPIUpg

[deuce_roadster]

After looking at all the pictures, the one of the transmission doesn't look right to me. You can see the brass synchro ring on the main drive gear but with the synchro sleeve in the second gear position it looks to me like there is way too much space between the 3rd gear brass and the synchro, more than the entire notch looks exposed. Maybe it is just the camera angle. Been a while since I put one together but maybe a trans expert will chime in.

[left.covst]

Originally Posted by deuce_roadster

After looking at all the pictures, the one of the transmission doesn't look right to me. You can see the brass synchro ring on the main drive gear but with the synchro sleeve in the second gear position it looks to me like there is way too much space between the 3rd gear brass and the synchro, more than the entire notch looks exposed. Maybe it is just the camera angle. Been a while since I put one together but maybe a trans expert will chime in.

Deuce - You're totally right, that was on disassembly and the input shaft had already slid forward out of the case, on re-assembly it was correct as seen here (attached).

[V8COOPMAN]

Originally Posted by left.covst

Might be an excuse to put a quick change center section in.

Be aware that a quickie will not live happily with the STOCK rear crossmember, without a bunch of crossmember surgery.

The noise you're hearing upon deceleration is what you can expect ANY TIME a pinion bearing is compromised in any way.

Coop

.

[left.covst]

Originally Posted by V8COOPMAN

Be aware that a quickie will not live happily with the STOCK rear crossmember, without a bunch of crossmember surgery.

The noise you're hearing upon deceleration is what you can expect ANY TIME a pinion bearing is compromised in any way.

Coop

.

Thanks for pointing that out Coop - Definitely saved me a ton of grief. Looks like a stock rebuild is in the cards in that case.

[bbrocksr]

Originally Posted by left.covst

Thanks for pointing that out Coop - Definitely saved me a ton of grief. Looks like a stock rebuild is in the cards in that case.

Coop is right , Pinion bearings. Anytime you have howl or growling noise on deceleration you can bet its pinion bearings,
Bill

[left.covst]

Originally Posted by bbrocksr

Coop is right , Pinion bearings. Anytime you have howl or growling noise on deceleration you can bet its pinion bearings,
Bill

Thanks Bill, appreciate everyone's help in confirming my suspicions. The noise was pretty apparent, but since I had so much apart I wanted to be sure it wasn't something else leading me astray.

Starting to make a list from the Van Pelt catalog and plan on some tools like a dial indicating torque wrench, seal driver, and hub puller for the job.

This tool kit from Mac's seems to be the right fit for my needs to pull the pinion bearings and double race themselves.

I also see suggestions that the Mitchell puller may be the preferable option.

Open to any other pointers or tools I should be thinking of outside of a press.

[ford38v8]

Originally Posted by left.covst

Thanks Bill, appreciate everyone's help in confirming my suspicions. The noise was pretty apparent, but since I had so much apart I wanted to be sure it wasn't something else leading me astray.

Starting to make a list from the Van Pelt catalog and plan on some tools like a dial indicating torque wrench, seal driver, and hub puller for the job.

This tool kit from Mac's seems to be the right fit for my needs to pull the pinion bearings and double race themselves.

I also see suggestions that the Mitchell puller may be the preferable option.

Open to any other pointers or tools I should be thinking of outside of a press.

One tool most essential to Early Ford mechanics is a fully stocked beer refrigerator.

[left.covst]

Well, it would certainly appear the nuts moved since I saw them last.

[cas3]

I always like to use a new lock washer there as the inside tab that locks to the shaft can break without you knowing, most likely what happened here.

[left.covst]

Originally Posted by cas3

I always like to use a new lock washer there as the inside tab that locks to the shaft can break without you knowing, most likely what happened here.

Unfortunately the boogered nuts and ring are the result of a previous individual, but it'll get fixed right!

[ford38v8]

It’s been a while, but I seem to remember that those locknuts come as part of the order along with the bearings for exactly that reason. They seem so inadequate for the important task they perform.

[left.covst]

Originally Posted by ford38v8

It’s been a while, but I seem to remember that those locknuts come as part of the order along with the bearings for exactly that reason. They seem so inadequate for the important task they perform.

I ordered fresh lock nuts, and an NOS lock washer. I had heard issues about the tangs on repro's catching the edge of the torque tube which may have been what happened here. Either way it seems to have been re-used too many times and bent all out of shape.

In either case I'll ensure they're firmly locked in place, not just to each other. I also ordered a dial Torqometer so I'll be able to correctly set the 15-20 inch pounds, and 1-7/8" wrenches to get the nuts properly done up. I added a Mac's Fab pinion puller as well to get that bearing race out.

[cas3]

NOS lock washer is wonderful. I thing some of the new ones are too soft, and if you are not paying attention you can break the tang off while snugging up the nuts.

[Mart]

Glad you found the cause. For those interested, the noise on the overrun is generated by the helix on the gear teeth sucking the pinion is and making the mesh too tight. Under power the pinion is pushed away from the ring gear. Hopefully the vehicle was not driven enough to cause permanent damage to the gears.

[Terry,OH]

I agree with post #9 there is a big problem with the transmission. In your first photo of the transmission you can see the front blocker ring appears to be stuck on the input gear. There is very little distance between the brass ring and the gear syncro teeth. When you look at the square U-shaped opening in the perimeter of the blocker ring it appears to be worn sideways most likely from the transmission being forced into 3rd gear. While you have the rear out for repair is a great time to work on the transmission.

[left.covst]

Originally Posted by cas3

NOS lock washer is wonderful. I thing some of the new ones are too soft, and if you are not paying attention you can break the tang off while snugging up the nuts.

Originally Posted by Mart

Glad you found the cause. For those interested, the noise on the overrun is generated by the helix on the gear teeth sucking the pinion is and making the mesh too tight. Under power the pinion is pushed away from the ring gear. Hopefully the vehicle was not driven enough to cause permanent damage to the gears.

Good to know! Definitely drove it enough to cause damage.

Originally Posted by Terry,OH

I agree with post #9 there is a big problem with the transmission. In your first photo of the transmission you can see the front blocker ring appears to be stuck on the input gear. There is very little distance between the brass ring and the gear syncro teeth. When you look at the square U-shaped opening in the perimeter of the blocker ring it appears to be worn sideways most likely from the transmission being forced into 3rd gear. While you have the rear out for repair is a great time to work on the transmission.

Hey Terry - See post #10, the picture in post 9 had the input shaft loose from the case itself. In #10 I posted a picture of it re-assembled.

[Terry,OH]

I noticed the loose output shaft and the bearing out of position causing a lot of space but my comments are bout the condition of the Syncro blocker ring.

[left.covst]

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Originally Posted by Terry,OH

I noticed the loose output shaft and the bearing out of position causing a lot of space but my comments are bout the condition of the Syncro blocker ring.

Got it Terry - They did seem to be in good condition with only a slight wiggle within the syncro block itself. All was tight upon assembly. I think I will leave it for now as there was no shifting/syncro issue going into third and it'd pain me to resplit that fresh transmission.

Reviewing that image referenced, I think it's more of a glare off the main shaft making it look like it's more worn that it truly is. If I end up digging back in for a failed syncro I promise I'll owe ya a beer.

[left.covst]

Got the rear end apart today once my hub puller arrived. All came apart well, but I was surprised to find only one left-side gasket and nothing on the right. It never did leak, but I can't imagine it was setup correctly.

I was also surprised to find a 3.78 gear set (34/9). Not sure if this is original or not, though I expect it is not.

No major carnage, though it looks like the pinion pushed its' snout bearing back a bit, popping off the bottom rivet for its' sheet metal retainer. I'll need to get that re-attached.Anyone have experience re-attaching or replacing with a 3/16" rivet?

I'm waiting on the pinion puller to extract the pinion, its' accompanying bearings, and the double race out the front.

My plan was to replace the ring & pinion, carrier & pinion bearings, and the carrier & pinion bearing races.

Could I get away with reusing any of the originals if they inspect well?

I'll also replace all seals and setup the axle with the correct number of shim gaskets, the right backlash, and the proper pinion preload.

A video of the pinion gear teeth is linked here: https://share.icloud.com/photos/00eP...pZ0y44Qwwfyfxg

[left.covst]

The more I look things over, the more I think I might get away with re-using the ring & pinion and the carrier bearings and races. I'll wait to extract the double bearing race and pinion bearings to make a call on those.

While there is some very light pitting on the carrier races and the R&P, generally the bearings themselves all seem to be in good shape with little to no wear on the rollers or cages.

R&P teeth seem to have some wear but nothing dramatic, save for some tooth edge chipping on the center diameter..

What are y'all thoughts? Too far gone or run-able?

I guess I'd ultimately know for certain when I go to setup all the dimensions but would love some opinions.

[Mart]

If it were me I'd run them but with the proviso that I'd be prepared to rework it if it proved to be noisy. To be honest a couple of mine are a bit noisy and I don't plan on reworking them.
3.78 is a decent ratio. If they were 4.11s I'd say look for something better.

Mart.

[cas3]

I'd run them. When they're set up proper there should be no contact at the end anyway. That happened when it was run loose

[left.covst]

Originally Posted by Mart

If it were me I'd run them but with the proviso that I'd be prepared to rework it if it proved to be noisy. To be honest a couple of mine are a bit noisy and I don't plan on reworking them.
3.78 is a decent ratio. If they were 4.11s I'd say look for something better.

Mart.

Originally Posted by cas3

I'd run them. When they're set up proper there should be no contact at the end anyway. That happened when it was run loose

Thanks guys - I feel the same here. The actual wear surfaces look good. I got the pinion bearing race, pinion, and bearings out today.

Here's a video of how they look. Feeling fairly confident re-using them after a good cleaning. The thrust washer showed some significant wear so I plan to replace that.

https://share.icloud.com/photos/058F...R_-LbK46hqGWAg

So I'll end up reusing the pinion bearings and race, carrier bearings and races, the ring and pinion, as well as the axles and center section components. I actually have a feeling that the bearing retainer / shield rubbing against the pinion gear edge is what created most of the filings I saw in the fluid.

I still need to figure out how I'll rivet a replacement shield back in place, would love any suggestions you all may have.

[V8COOPMAN]

Originally Posted by left.covst

Thanks guys - I feel the same here. The actual wear surfaces look good. I got the pinion bearing race, pinion, and bearings out today.

Here's a video of how they look. Feeling fairly confident re-using them after a good cleaning. The thrust washer showed some significant wear so I plan to replace that.

https://share.icloud.com/photos/058F...R_-LbK46hqGWAg

So I'll end up reusing the pinion bearings and race, carrier bearings and races, the ring and pinion, as well as the axles and center section components. I actually have a feeling that the bearing retainer / shield rubbing against the pinion gear edge is what created most of the filings I saw in the fluid.

I still need to figure out how I'll rivet a replacement shield back in place, would love any suggestions you all may have.

I don't believe those are rivets. My GUESS is that they are some form of a twisted-flute nail, similar in concept to that seen BELOW, although shorter. I've been wrong brfore. Nevertheless, you could always drill and tap for something like a #12 screw, or similar.

Coop

[left.covst]

Originally Posted by V8COOPMAN

I don't believe those are rivets. My GUESS is that they are some form of a twisted-flute nail, similar in concept to that seen BELOW, although shorter. I've been wrong brfore. Nevertheless, you could always drill and tap for something like a #12 screw, or similar.

Coop

Thanks Coop! I thought the same but they are in fact rivets, pushed in from the back and then peened over on the front. Here's the removed one attached.

I ordered some 3/16 x 5/8 pop rivets to see how those fit.

Just dropped the radius arms, torque tube, center section, axle bells, and the driveshaft off for blasting and powder coating today, hoping that all comes out nicely.

[ford38v8]

Originally Posted by left.covst

Thanks Coop! I thought the same but they are in fact rivets, pushed in from the back and then peened over on the front. Here's the removed one attached.

I ordered some 3/16 x 5/8 pop rivets to see how those fit.

Just dropped the radius arms, torque tube, center section, axle bells, and the driveshaft off for blasting and powder coating today, hoping that all comes out nicely.

Zach, Mask the gasket surfaces and interiors well. Nothing like a little sand in sensitive areas to ruin your day.

[left.covst]

Originally Posted by ford38v8

Zach, Mask the gasket surfaces and interiors well. Nothing like a little sand in sensitive areas to ruin your day.

I did my best to communicate the important ones to the powder coater, but honestly expect I'll need to do a ton of dressing/cleaning when I get the parts back.

It's a bummer but quality work isn't the most common around the bay area in general.

[ford38v8]

Originally Posted by left.covst

I did my best to communicate the important ones to the powder coater, but honestly expect I'll need to do a ton of dressing/cleaning when I get the parts back.

It's a bummer but quality work isn't the most common around the bay area in general.

It's not just cleaning, the blasting will destroy your gasket surfaces, and change critical dimensions.

[left.covst]

Got my parts back from coating, very happy with how everything came out. Masking was well done and it's all nice and clean.

I'm going to give everything a quick rinse to get out any blasting media and start re-assembly. I was able to get the bearing retaining plate reinstalled with some 3/16 x 1 rivets. I should've gone a bit shorter but they don't seem like they'll touch the pinion at all.

Looking forward to getting it all back together and on the road!!

[ford38v8]

Looks like your blaster didn't get the memo. Sorry about that.

[sugarmaker]

Zach,
Welcome to the content portion of the Ford Barn, your doing great with the pictures and updates on your work. I hope this comes out better than expected and wor4ks good and lasts a long time too. Wow the powder coated parts look good. I am not in any way a judge of rear end assemblies. So that I will leave to the experts here! I do like your truck! Very sharp! I would drive that!
Merry Christmas!
Regards,
Chris

[V8COOPMAN]

.

Make sure that when you do re-assemble the torque tube to the banjo housing that you get the drain-back hole in the housing (indicated by the pencil) lined back up with the slot in the rear flange of the torque tube,

Coop

[left.covst]

Originally Posted by ford38v8

Looks like your blaster didn't get the memo. Sorry about that.

I was actually pleasantly surprised - the main mating surfaces were cleaned up but not overly blasted.

Originally Posted by sugarmaker

Zach,
Welcome to the content portion of the Ford Barn, your doing great with the pictures and updates on your work. I hope this comes out better than expected and wor4ks good and lasts a long time too. Wow the powder coated parts look good. I am not in any way a judge of rear end assemblies. So that I will leave to the experts here! I do like your truck! Very sharp! I would drive that!
Merry Christmas!
Regards,
Chris

Thanks Chris, Merry Christmas!

Originally Posted by V8COOPMAN

.

Make sure that when you do re-assemble the torque tube to the banjo housing that you get the drain-back hole in the housing (indicated by the pencil) lined back up with the slot in the rear flange of the torque tube,

Coop

Thanks Coop - I actually have a baffle in that area from Danny Burroughs to keep the oil from making its' way up my torque tube, so I also have a vent added to the left axle tube. I did line the slot up regardless.

Today I got all the work finished up and truck back on the ground! Axle re-assembled and running smoothly. I have about 10 miles on it so far but will keep logging some miles and report back on anything exciting.

I owe some better pictures now that's it is moving again, but took a couple videos as well:

Happy Holidays all!

https://share.icloud.com/photos/03fG...R6tOPhZPkO1pTA

https://share.icloud.com/photos/0beT...dbYLjs-3EHBxbA

[pistonbroke]

Hi Zach,
I enjoyed this thread and it's timing was perfect . My Mitchell overdrive is here and I'm ready to dive in. I've been in the front of the torque tube ( U joint) but never at the rear. After following this thread and a few older ones it doesn't seem to tricky to me. I did notice you dropped your leaf spring with the rear end rather then popping the shackle's. Your thoughts?
Tim

[left.covst]

Originally Posted by pistonbroke

Hi Zach,
I enjoyed this thread and it's timing was perfect . My Mitchell overdrive is here and I'm ready to dive in. I've been in the front of the torque tube ( U joint) but never at the rear. After following this thread and a few older ones it doesn't seem to tricky to me. I did notice you dropped your leaf spring with the rear end rather then popping the shackle's. Your thoughts?
Tim

Hey Tim! Glad it was helpful. It's not too intimidating once you get in there, and there are a ton of resources on the barn and other sites to help guide you through. I used Tom Endy's guides, as well as threads here and on HAMB to inform myself before diving in. Once you break everything down it's not too scary.

I also found this video, which is very relevant to you!

I'd note you may need a few tools - Axle seal installer (which you thread on the end of a 3' pipe to install the two outer bell seals), an inch pound torque wrench (I bought a used SnapOn Torqometer on ebay), dial indicator (to assess backlash), hub puller (to get the brake drums off), pinion nut wrenches, and a pinion bearing / race puller.

With my spring, I was thinking I'd need a spreader, but I realized pretty quickly the tension wasn't strong enough to warrant it. This is definitely a "mileage may vary" type of situation though, as I know the springs have potential to be very dangerous. Mine is lowered and is definitely a non-factory spring.

In my case I dropped it with the axle, then simply popped off the shackles and the spring only moved about a half inch. While putting it back on I didn't need to apply any effort to get it lined up, it just dropped into place. In retrospect I could've left it attached to the crossmember, but having it out and accessible let me assess whether it was safe to remove without spreading or not.

Let me know if you have any other questions as you dig into it!