Deuce driveshaft extension for 4x4

[tobyS]

DUST SEAL, INTERMEDIATE DRIVESHAFT

I need to replace the dust seal for the spline (slip yoke) on the TC to first axle driveshaft. It appears to be a hard felt material, has a washer and screw on cap. I can get by with just the seal. It is split on the side because it won't go over the spline. I can't find it commercially.

 

[goodwithwood35]

Email big mikes motorpool the NSN#, he can probably get it.


Sent from my iPhone using Tapatalk

 

[frank8003]

a picture for the General

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[tobyS]

I don't know frank. I would think the tranny to transfer case drive is the same size and shaft dia., but made a similar mistake with the one between the axles. It (inter-axle) is not the same size.

Here is what I need it for. I have a new spline and slip yoke in 1410 size coming for the second shaft. the new one has a seal. I decided to use slip joints on both front and rear of the two piece I'm building, transition at the (3") tube.

What do you think about using a pillow block or flange, a solid mounted bearing, at the carrier?

Edit....still looking for the new spline shaft seal for this slip yoke assembly (have a wanted part ad). G provided the following numbers:

Early part# 7369953
Later part# 10874585 (NSN 5330-00-108-9651)

 

[tobyS]

I started this thread for the driveshaft of my M35A3 4x4 project. I did not shorten the frame and I have positioned the axle to be on the center line of the wheel well for an M105 bed that has 3" overhang at the frame rear. The CL is 50" from the rear of the trailer which makes the axle CL 47" from the rear of the frame.

With the axle now located in that position, the driveshaft is around 84". The deuce uses a 3" tube, which makes a difference in the shaft build. Using the "critical speed" calculator for 3" and 84" the max CS is only 1700 rpm. I read that the Cat is often pushed to 3000 (not that I will), is way too far to even consider a one piece. Likewise I entered the 3.5" size and it was not much better.

I made a mistake when planning the two piece DS, I thought the intermediate shaft between axles was the same size as the one from TC to the first rear axle that I needed to lengthen. I ordered a spline shaft with a carrier bearing with 1 1/2"- 16 spline for 3" tube, thinking it was the same as the OEM slip yoke pictured here. It's not.

To further complicate, I found the 1500 series (Spicer 5-115) series u-joint style driveshaft components that are OEM on our trucks are not available. Searching for weld yokes for about a week turned up one used and I needed two...and I was still thinking my outer slip yoke was 1.5-16. I did find one at a supplier at an uber high price...glad I didn't buy it.

I discovered the difference when I took the slip yoke apart. OEM (1500 series) is a 1 3/4 -16 spline and would not fit the new spline on the carrier bearing shaft....nor was one available at suppliers that would fit the 1.75".

C & C sells a kit for using the 1480 series U joint and for a good beefy drive-line, 3 1/2" diameter, that would be a good selection, but a route I did not take. As I had a 72" new stick of 3" tube and the 1 1/2-16 spline and carrier bearing, I decided to stay with the 3" tube that is OEM on our trucks....at least for this two piece driveshaft.

The 1410 series is well capable for the HP that my Cat/Allison puts out and is cheaper than the 1480...a lot. The 1 1/2-16 spline slip yoke is available with the 1410.

Shazam !!! The 1410 series u-joint can be combined with our OEM driveshafts at the tube connection, both being 3"x .083". The second picture is of the plated U-joints (1500 OEM style)(another reason I wanted to use the 3").

 

[tobyS]

Now the components are ordered to use the 1410 series u joint, 1.5"-16 spline and 3.0"x.083 tube, with 1.5" carrier bearing.

I've researched driveshaft systems and found that about half have a slip-joint in the first section (usually an AT) and about half use only a u-joint before the carrier.

The first section of the DS is supposed to be in line with the output of the transfer case. Under ideal conditions there would always be perfectly straight alignment and no need for lateral flex, at least more than the rubber mounts of the bearing can absorb, but that doesn't take into account any frame flex or flex in the TC mounts.

If our transfer case had a slip joint (spline) like an automatic, there would be no problem, but I fear putting end pressure, pulling or pushing on the TC bearings would not be a good thing. Thus, not only the second shaft attaching to the axle will have a slip joint, but the first shaft will also. Photo compares with slip joint and without, both using the carrier and mid-shaft.

 

[tobyS]

I would like a more robust bearing for the center support, does anyone see a reason that I could not use a pillow block or flange bearing? There would be no lateral pressure for the rubber to absorb and I do plan on having it balanced.

 

[CMPPhil]

Alternative Material for the Slip Yoke Seal

Hi Toby

The split cork seal is very similar to valve stem packing used on large steam valves, that was very common years ago, it was replaced by Teflon Stem Packing which I have used on my CMPs for years.

The goal of course is to have a packing matierial that can slide smoothly up and down the drive shaft while keeping the dirt and the grease in the slide joint apart. Which the teflon stem packing seems to do very well. Nice part of the Teflon is it is soft enough that you can wrap it around the shaft till you have enough to fit the slide nut over it and tighten the nut. If you tighten the too much the teflon may extrud out, not a problem just back off and add a little more.

If you try this let us know what you think.

I've got many years and thousands of miles with this trick. The check to see if teflon needs to be replaced is when you grease the slide joint the excess grease comes out around the nut instead of the bleed hole up in the throat of the joint.

The advantage of the of the teflon stem packing is that you probably can find it at well stocked hardware store.

Cheers Phil

Better yet, after posting this I wanted find a picture of the Teflon Stem Packing what I found was square teflon packing, application marine prop shaft packing.

 

[tobyS]

Thanks CMPPhil....that should work. The same site has 1/4" too. With 3' (minimum in 1/4"), I can make about 20. I knew I recalled a square packing but couldn't remember what it was for. Thanks again.

www.westmarine.com/buy/sierra--premium-square-marine-teflon-packing-diameter-1-8-length-3--P010519924?pCode=10519890&mrkgcl=481&mrkgadid=3076578814&cm_mmc=PS-_-Google-_-GSC>NonB>Product%2520Type-_-10519890&product_id=10519890&adpos=1o1&creative=108421551724&device=c&matchtype=&network=g&gclid=EAIaIQobChMIx-qNifvy4QIVEdvACh1dsA3aEAQYASABEgKjyfD_BwE

 

[tobyS]

Parts came in to start assembly of the new shaft. I still have not decided on the carrier bearing. I have a rubber mounted one but I'm leaning towards a flange bearing, solid or cushioned mount for more rigidity.

CMPPhil, I was looking at the local hardware for the packing like you mentioned and came up with a seal. It was in the farm ag chemical plumbing section, a square 1/4 x 1/4 rubber for a 2" plastic pipe seal. With the handy exacto I have my drive seal, under $2.

The first portion or the new shaft is being welded and will be installed so an accurate length from u-joint to u-joint can be measured and made to length.