1960 B75 Mack

[Truck Shop]

Finished the 15spd, had to machine a 14613 rear bearing retainer to be able to install a magnetic pickup for speedometer. Parts for these older gear boxes are getting hard to find.
Finished the engine also, completely wired and plumbed so when it comes time to set it in the frame, connections will go pretty fast. And I finally got the headlight buckets repaired
and polished. The right one was cracked from headlight opening to fender edge the other one had a piece broke out of bottom next to radiator housing. A bunch of time in cutting
and fitting a piece of 3/8 aluminum stock to repair it then carefully blending that area to match. 30 hours -maybe less time involved in those two items. Next job is remove the
rear drives and tear those down and inspect.

Truck Shop

 

[Truck Shop]

If you look at page one you will see the broken spot

Truck Shop

 

[Junkyard]

Looks great!

 

[DMiller]

WOW!!

 

[colson04]

Your attention to detail is exceptional. You are a true master of your craft, Truckshop.



What kind of paint do you use on the engine and transmission?

 

[Truck Shop]

Your attention to detail is exceptional. You are a true master of your craft, Truckshop.



What kind of paint do you use on the engine and transmission?

Thank you.

It's nothing more than rust red primer. It actually lasts as good as anything else plus if it has a leak it's easier to spot.

Truck Shop

 

[crane operator]

Somebody has a wonky homemade plate on their transmission jack

. I keep saying I'm going to build a bracket for the top of mine, and then I always just end up shoving it up there and ratchet strapping the transmission or rear end to the top.

Mine has the two round pipe bars on the top, I think its a old walker. It may be older than I am. Still works good. I see the new ones have just a flat metal plate, and I always wondered how well that works, or if everyone just ends up putting adaptors on it.

 

[Wes J]

My OTC has a flat plate with one bent flange to match most twin counter shaft transmissions. All bets are off when trying to pull something with the PTO in place or a Mack with the 3 shafts.

 

[DMiller]

The one I used for years in OFallon Mo was a Walker, had several tables for it where had installed chains to hold the trannies secure or sort of. Used all fashion of cribbing under trans with PTO or odd shapes as the old Clarks and a few Spicers. We also used it when could on differentials, run them out on drive screws where could get the lip on the table behind the case flange then chain thru the yoke to kinda sorta keep it in place. We made several sets of support ears from angle iron for that app.

 

[RZucker]

The one I used for years in OFallon Mo was a Walker, had several tables for it where had installed chains to hold the trannies secure or sort of. Used all fashion of cribbing under trans with PTO or odd shapes as the old Clarks and a few Spicers. We also used it when could on differentials, run them out on drive screws where could get the lip on the table behind the case flange then chain thru the yoke to kinda sorta keep it in place. We made several sets of support ears from angle iron for that app.

Yep, I try to use angle iron of a suitable dimensions to cut a cradle for the oddballs.

 

[Truck Shop]

Actually that plate came with that transmission jack, I had to notch it for later model Eatons. Best jack I ever used, high lift-works great for rebuilding. But If it's not a
twin counter shaft I really want nothing to do with it anyway. Kind of picky about the gear boxes I will work on.

Truck Shop

 

[Junkyard]

Mine has a flat plate. I’ve made adapters for third members. It sure his handy to have around. I don’t recall what trans I did awhile back. Had to cut some wood wedges and use a strap to keep it on there.

 

[Truck Shop]

It's been around 25 years since the last time I worked on a set of SQHD's. Removed from housings and inspected today-pretty decent shape and the ratio is 3.70 which is exactly
what I wanted. The only thing the rear-rear drive needs is just a touch of preload on the side carrier bearings and the pinion seal replaced. The main reason to disassemble the
front drive was to check the pinion nut on pinion drive gear, it's tight and staked. It would be totally foolish to bypass checking that nut-a typical problem with this model of rear
drive. If that nut gets loose all kinds of misery happens-it can burn/bore a hole through the front housing. But other than some discoloration from old gear lube the front drive
is in really good condition. The 3.70 ration will work real well with the overdrive 15 speed. About 86 to 90 mph depending on tire size.

Truck Shop

 

[DMiller]

Look good, no debris in the Nose Housing pocket to indicate bearing issues, not much in these to otherwise go wrong. Were just a taste light in the day. Forward unit bolted ring rear is riveted. I have worked a 100 ton shop press long and hard cold upset riveting rings in these and the old Corn Queen diffs. Still get much in as much parts for them?

 

[Truck Shop]

But for what a SQHD was it could take a beating. The one that had trouble was the rear-rear SQHP with the long pinion. If the lube level was a tiny bit low it could roast the nose bearing.

Truck Shop

 

[DMiller]

Still remember the first P series we put in service in SLC UT, when they were run in severe cold and the relief would stick then blow the filter canister into eternity, of course then cooking the whole front unit, went to different weight multi viscosity lube and had pallets of front units sitting at the home office shop to send where they failed..

Was working in a quarry pit Aug.1984 trying to free a hung in two gears Euc, got told of a Brand New style KW Anteater smoking a transmission, then the cascade of fullers burning up from all the aerodyne skirting across the whole heavy truck builder list, the onrush to get coolers and external pumps adapted to them, boy those were the days.

 

[Truck Shop]

What really killed them was engine torque spec's going higher and the transmission torque ratings lagging behind right along with clutch ratings. Then finally Eaton
went to tapered bearings on the counter shafts in the back section. The old ball type couldn't stand the torque and pressure pushing the counter shafts outward.
Plus higher tooth count on the gears in the front section and helical gears in the rear section. And better heat treating of gear teeth. Make me laugh-the old
Cat 1693 425 HP 1400 ft lbs torque came with a RTO 9513 spd from factory. Funny thing is those old 95's took it.

Truck Shop

 

[RZucker]

What really killed them was engine torque spec's going higher and the transmission torque ratings lagging behind right along with clutch ratings. Then finally Eaton
went to tapered bearings on the counter shafts in the back section. The old ball type couldn't stand the torque and pressure pushing the counter shafts outward.
Plus higher tooth count on the gears in the front section and helical gears in the rear section. And better heat treating of gear teeth. Make me laugh-the old
Cat 1693 425 HP 1400 ft lbs torque came with a RTO 9513 spd from factory. Funny thing is those old 95's took it.

Truck Shop

I recall a '69 Pete COE with a 12V71 with a 9513 behind it, that was the most trouble free part of the truck.

 

[DMiller]

Seen the same here Zucker, as with KT series Cummins besides. Pig Iron Express had 12V DD KW units and later 8V92s in Petes with 9513s in them pulling triples out of SLC, when they were not tipping no.3 over on the highway ramps!!

 

[DMiller]

Had to be careful in the 'Olden Days' not to put mineral 90 in the Spicer single countershaft boxes as they used heavy motor oil 40 or 50wt Non Detergent, a few oddballs used Type A ATF which was Whale Oil!! then the twin shaft units that used 90 mineral or heavier weight motor oils and these days the synthetic multi vis oils as 75w90 or straight 40w not to mention the semi-autos with ATF types. Need a damn score or dance card BOOK to keep up and a inventory of dozens of products anymore if have Old School machines mixed in.

What are most using in 3rd members these days, I was accustomed to the 85/140 lubes of days gone by, these are also changed as I am aware. Do the old gear boxes(Mack/Eaton/Rockwell) tolerate the new lubes very well?