How To: C15a Wire-3 restoration

[Jordan Baker]

Some more pictures of the greasy bits.

[Bruce Parker (RIP)]

The inside looks pretty good. The things to look out for are slop where the main shaft inserts into the front input shaft, and that the reverse gear slides well its shaft. Apparently this gets little lubrication and can bind. All bolts on the rear cast (or white metal) bearing cap need to be snug as the output flange will sheer off the bolts and crack the cap if not. Have a good look at the cap to make sure it isn't cracked already as many are.

[Jordan Baker]

Left the housing sitting in a bucket of degreaser solution for a few hours. Took it out and scrubbed it down then hosed it it off with a hot water hose. I then used a wire wheel to clean it up and remove the surface rust. I still had to go back with some small scrapers and aresol parts cleaner to get a few hard spot. Man that 75 years of grease really gets hard. Some spots were like chipping cement. Lastly brought it inside and washed it down with the marine clean from POR and then some metal prep to get rid of any final rust.

Now the hard part what colour to paint it? From what I have read here on the forum they may have come Chevy grey, semi gloss black or even have been painted the final body colour of LG#3, SCC2 or SCC15

[Phil Waterman]

Hi Jordan

I bought a NOS transmission a couple of years ago and it had been sprayed or dipped in cosmoline which had dried out. Took same sort of treatment soaking with degreaser then washing down with 160F hot water to get it clean.

You nailed the problem of cleaning hot water works much better than cold or even room temp.

How do all the bearing look? Was there any sign of water having been in the case, ie any pitting on the gears?

Enjoy your restoration reports.

Cheers Phil

PS I've painted the last couple of transmissions after assembly but before adding gear oil with Por15 black. Seems to help seal the gasket edges from leaking.

[Jordan Baker]

Thanks Phil

There was some very minor rusting on two of the gear right at the bottom of their rotation. When I drained the oil about two teaspoons of water came out first. I’ve ordered new bearings via eBay yesterday. Will hopefully have them next week. The bushings in the reverse gear are still in great shape with no side to side play on the shaft. I’ve cleaned up the gears using a brass wire wheel on an electric motor. That removed all of the rust scale. There is no pitting and very minimal wear on the gears. The cast bearing retainer housings were also polished up on the brass wire wheel. I’ve got all of the bolts and washers being cleaned up in my media tumbler. All in all this has gone smoothly.

For my colour I decided on using Ford Grey. I know I know but the online Chevy folks say it’s a good representation of the Chevy grey. I also figured the lighter colour would be easier to spot any leaking.

[Jordan Baker]

The cast parts and gears all polished up.

[Bob Carriere]

...."I’ve ordered new bearings via eBay yesterday". ......

these are the two lower one I assume...... were they visibly pitted..? curious about the rear bottom one which was problematic to match a few years ago. Could you share how it fits and possibly the source.

On the gears....... I took a fine diamond stone and went over the leading point of the teeth one by one to reduce the wear pattern evenly .....cause by crash shifting in its previous life.....sometimes only a few needed some minor dressing....hoping it would help my shifting in the future.

Have you decided on the oil you will use???? I have used synthetic from Lucas and as predicted it tends to leak ever so lightly...... a particular feature of synthetics is the ability to creep into tiny crevices/space. .....but then it is a CMP and they love marking there territory.

Bob C

[Jordan Baker]

I just went by the part numbers and the cross reference numbers Rob Love had dug up. I ended up getting all 5 bearings on eBay. As for the originals. Yes the bottoms ones had rusting and some rust flakes inside them. The upper ones look ok but I figured with it all apart I may as well replace them too.

I haven’t looked that far ahead yet for what oil I’ll use. My Willys MB seems to like the 80/90 transmission hypoid oils.

I compared my gears to some NOS ones on eBay and found mine were looking pretty much the same.

[chris vickery]

If in doubt bead blast the gears which will reduce stress in the steel

[Bob Carriere]

It's the bottom rear bearing.......keep me posted of what that bearing looks like and how well it fits.

Thanks

Bob C

[rob love]

Originally Posted by Jordan Baker

I haven’t looked that far ahead yet for what oil I’ll use. My Willys MB seems to like the 80/90 transmission hypoid oils.

Not all hypoid oils are the same. The most current spec of hypoid is GL4 edited to add: now GL5) which is reported as harmful to brass. Not a problem for your Chevy crash box, but any transmission with synchro rings may not have a happy ending.

What belongs in those is GL1 or possibly GL3 specification. Tough to find...ask any Dodge Diesel owner with a manual transmission. I ended up using royal purple.....expensive, but cheaper than removing and repairing the transmission.

Bob: I always considered the oil leaks on a chevy quite standard. Many of them here at the museum feature multiple drain pans underneath them.

[Robert Bergeron]

Rob/ Jordan : Gl4 could explain the early demise of the 2 nd gear and it’s brass syncro ring in my GPW transmission a couple of years ago ...

[Lynn Eades]

A friend of mine is just replacing a new jeep trans. with a new jeep trans. (1000km) Reason: Incorrect oil. The Hypoid oil ate the bushes in the cluster.

Jeep has bronze bushes inside the cluster gear (counter or lay shaft) and the reverse idler as well as the synchro (baulk rings) The Dodge (New Process) and Ford 4 speed crash boxes have a bush in the reverse idlers. I assume the G.M. box has bronze bushes in the reverse idler as well.

Also, bead blasting is great for the gears as stated, but!.... Total cleanliness is absolutely imperative, after blasting. It gets everywhere!

On both counts, Beware!

[Wayne Hingley]

Hi Rob: Is this the Royal Purple product you are using? In your research, did you find any other non-EP gear lube options?

http://www.royalpurpleconsumer.com/p...mission-fluid/

[Jordan Baker]

Today I took apart the top of the transmission. It was in dire need of some cleaning on the outside and at the base of the shifter. Some very very thick crudy grease. The inside looks great though. Everything came apart nicely. My only concern was that the reverse shifter yoke looks worn.

It’s part number 4.303 GM590515 Yoke reverse shifter.

The parts are all soaking in parts cleaner to help soften the hard grease.

[Alex van de Wetering]

Great work again, Jordan

Now the hard part what colour to paint it? From what I have read here on the forum they may have come Chevy grey, semi gloss black or even have been painted the final body colour of LG#3, SCC2 or SCC15

I also painted mine grey recently....and just like you I thought that would be great for spotting leaks, but I am now thinking about respraying it body colour...as that's what i think I am seeing on the factory pictures.

Alex

[rob love]

Originally Posted by Wayne Hingley

Hi Rob: Is this the Royal Purple product you are using? In your research, did you find any other non-EP gear lube options?

http://www.royalpurpleconsumer.com/p...mission-fluid/

The Q&As at the link you show says it is fine for the soft metals. I am using the 75W90 that is available at Cdn tire. My transmission shifts nicer with it, and everything I could find on it was that the synthetic was fine for the synchros.

I think Boss lubricants still sell GL3. Seems to me Dodge and the other likely will too, but pretty sure theirs will be as much or more than the Royal Purple.

[Jordan Baker]

I went out and checked on what I’m using. I was mistaken. I’m using the 75/90 stuff from CND tire as well.

[Wayne Hingley]

Thanks gentlemen. I looked up the info on the Royal Purple (Max Gear) 75w90, and it does mention that it is yellow metal safe. Ill be switching my lube this weekend.

I suppose the same would be true for the steering box, PTO and winch lubes. Is there any yellow metal in the differentials?

http://www.royalpurpleconsumer.com/products/max-gear/

[rob love]

Originally Posted by Jordan Baker

I went out and checked on what I’m using. I was mistaken. I’m using the 75/90 stuff from CND tire as well.

When I said "stuff", I was relating to the royal purple....not the Cdn tire house brand.

[Jordan Baker]

I also found that one of the fulcrum pins in the top of the shifter housing was rather worn and very loose. NOS pins have been ordered and I’ll be replacing them both.

One area of concern is that the slots on the shifter may also be worn. However I don’t have any reference to compare by. At least until I get the NOS pins. If I find the slots are worn exceisvly my idea is a follows. Mount the shifter in the mill and true up the slots. It may make them a slight bit larger. This would require a slightly larger pin. My thoughts are to use some round stock from a suitably sized drill bit shaft and turn down the one end in a lathe. This way I’d be using slightly oversized pins to fit the slightly oversized slots. What are the thoughts of the membership?

[Bob Carriere]

At least if you grind the teeth on shifting you can blame the worn parts.

I cannibalized parts from spare trannies and used section of the PA Chinese drift punch shaft for hardened pins. In fact we were reproducing CMP engine cranks on the week end and we used a battered drift punch to produce two pins for the crank.

Good luck with the tranny.

Bob C

[Barry Churcher]

I have always used 50W motor oil in all my customers and my own transmissions and have never had an issue.. From Muncie 4 speeds to Clarke 5 speeds etc. 50W oil is the same viscosity as 80/90 gear oil but is a little more prone to creep so you need good seals and gaskets. This does not apply to the newer vehicles as you should use vehicle specific fluids. Even in the old B series, 2 stick Macks we used 50W.
Barry

[David Dunlop]

Just a thought, Jordan, but could you add metal to the sides of the slots and then mill the slot back to match the NOS pin?

David

[Jordan Baker]

Did a bit more work today on the transmission. On the one I’m rebuilding the interlock plate on the underside of the top piece was badly worn. This I believe was all as a result of the loose fulcrum pin. Anyway I looked over my spare transmission and the plate although a bit rusty was in very good condition. I took it all apart today pressing out the shifter fork shafts. I sandblasted the case only to discover a crack in the cast housing. I’m not sure, but I may have done that while pressing out the shafts on the press. I’ve since sheared off the 4 rivets holding the plate in place. And will be using the good plate on my good upper housing. This part was replaceable per the manual. However I’ve been unable to locate a NOS one. So I’ll be using the good one.

[Jordan Baker]

I also have two different lengths of shifters. I’m not too sure what is the most correct. The manual lists two different ones.

[Bob Carriere]

.... I have spare covers if you need one.....

I also have an assortment of shifters...... personally I prefer the longer ones if you need a replacement let me know.....and note some rebuilt tranny unit have the shifter reversed....!!!!

Have you tried the rear bottom bearing yet...?

Cheers

[Jordan Baker]

Hi Bob

Thanks for the offer. Ill see how the riveting goes in a couple days when Im off again from work.

I have not got the bearings yet. Ill probably go later this week to pick them up from the states.

[Jordan Baker]

The riveting went very well using the press. The good shifter interlock plate is now securely in place in the good housing.

Yesterday the NOS generator armature arrived in the mail. So this morning it was reassembly time on the generator. All went well. My only hang up was I forgot to take some pictures of how the wiring goes together.

[Jordan Baker]

Some more bits done.