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When requesting info or offering info regarding pilot bearings and pilot tools, it helps to clarify which gearbox we're talking about, because the Dash 1 and Dash 2 input shafts have differing dimensions.


ZF Model .... Pilot Bearing ... Input Shaft
------------------------------------------------
5DS-25/1 ... 15mm ............ 1-1/8”/10 spline
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5DS-25/2 ... 17mm ............ 1-1/16”/10 spline

The clutches require different friction plates too, for the same reason (input shaft size). The transition to the “dash 2” transaxle took place in February 1972, approximately chassis 2600. The Dash 1 is attached to the bell housing with 4 symmetrically placed studs, whereas the Dash 2 is attached to the bell housing with 5 studs. Since the gearboxes are oriented upside-down in the Pantera, this difference can be easily seen, making them easy to distinguish from each other.

-G
Last edited by George P
Besides the good advice from George, take a magnet with you when shopping for sintered-bronze pilot bushings. There are THREE different types and the correct one, the all-bronze one, may be hard to locate. The others are adulterated with so much iron powder that they are MAGNETIC. Such bushings will scar up the end of your $2800 clutch input shaft which really cannot be repaired. If a non-magnetic bronze bushing cannot be located and you have access to a lathe, one for a Chevy V8 from Lakewood Industries will fit but needs a 1/2" thick precision machined adapter ring, as the Chev part is too small in the OD as-stock to fit a Ford crankshaft. The ID is correct for a ZF input nose, however. The Chev bushing will be a press-fit into the ring while the ring will be a press-fit into the Ford crank
What about the part that Dave provided that is readily available from anyone that sells Dorman products.

I really find it hard to believe that the input shaft bushings that have been working fine for years on other vehicles will damage a ZF input shaft.

Are people saying that the input shaft on the ZF is made of a soft material that is damaged by the small amount of iron that may be present in some pilot bushings.

The only time there is any movement between the pilot bushing and the input shaft is when the clutch is depressed. That amount of time is so small that I find this issue to be hard to believe.

Has anyone ever seen this as an issue in the real world?

I hear the same thing about not using roller bearing pilot shaft bushings because if it failed it would destroy the expensive input shaft. The only thing is, I have never seen one fail.

Seems like Dave has the easy answer...

Scott (not worried about the pilot shaft bushing)
Scott,

Good points. I have built at least 50-75 ZF transaxles (5 and 6 speed,-1 and -2 ,M1 and RBT) and I have never seen an input shaft that was damaged by a bad pilot bushing. I have ,however seen a few B/W T5s from Mustangs and Camaros that have been damaged by roller bearings failing. Most have been in cars that were used very hard though.

Ron
Scott, it's not a 'small' amount of iron in those things. Two of the 3 common Oilite bushing formulations use at least 75% iron powder in their makeup and thus are strongly magnetic. These are not 'bronze' bushings, they are sintered IRON bushings, with a little copper and no tin. Copper and tin make up bronze alloys. Below from Wikipedia:


Oilite SAE 841:
87-90.5% copper, 9.5-10.5% tin, max 1% iron, 1% 'other'. Soaked in engine oil after mfg.

Super Oilite:
18-22% copper, no tin, 76-80% iron, 2% 'other'. Soaked in Turbine oil after mfg.

Super Oilite 16: 18-22% copper, no tin, 74-78% iron, 2% graphite, 2% 'other'. Soaked in Turbine oil after mfg.

Some pilot bushing wear comes from mis-drilled or mis-machined bellhousings so the register surfaces are not perfectly parallel to the crank, which is why speed shops sell offset bellhousing dowels so they can be trued up using a dial indicator. There are also deflections in any clutch input shaft whenever you are in the lower gears and power flows down from the mainshaft to the countershaft. If there were no side-forces or mistakes in parts alignment, real bronze pilot bushings would never wear out..... but we know they do, fairly quickly, so there must be some side-forces for whatever reason.

Given the extreme cost of ZF replacement parts, I'd rather error on the side of caution. So I NEVER use nor recommend ball or roller bearings as pilots, and I avoid using 'iron' bushings in any engine. YMMV....
quote:
$8 or $85 for a pilot bushing depending on your level of risk management.


LOL... Good one Mark.

I ran a roller bearing with my Cleveland and Dorman input shaft bushings for years on many cars. I could see Rons point about how the roller bearings could cause damage if they fail but I don't think the bushing will cause any damage. You will feel a large vibration if it starts to wear. I am just not worried and have not heard of any input shaft damage from any type bushing.

Too each their own. I like to live on the edge. I think I will take my chances and spend the 8 bucks next time I need one.
Thought I'd look a little at these, I found the measurements all over the place,
Of coarse if you do not understand clearances and tolerances and it happens to fit loose and it works,
well I guess you have luck on your side.I like Marlin am a Machinist and just naturally like a proper fit.
Whats $85.00 when the sizing,material is right. I'm glad we have some tradesman offering their expertise and efforts to provide parts especially on something that could be expensive to repair.
My 2 cents, Mark

Dorman Motormite 14656 Clutch Components, Clutch Pilot Bushings & Bearings Features:
• Clutch Pilot Bushings & Bearings
• Type: A
• Inside Diameter: 0.673"
• Outside Diameter: 1.380"
• Length: .565"
• Footnote: *
• Application: Ford

-----------------------------------------------------------
E bay
Clutch Pilot Bushing
Notes: Description--PILOT BSHNG .672X1.3

-----------------------------------------------------------

Ford Mustang 1970, Powder Metal Clutch Pilot Bushing (14656) by Dorman®, 1 Piece. Use 1 per Car. Package Type: Card. Inside Diameter: 0.754". Outside Diameter: 1.056".

-----------------------------------------------------------
Now you have given me one more thing to worry about.

I bought the engine I am using years ago assembled by a friend I trust, He was going to use it in a project car he did not ever get around to. I have it out now to make some modifications. I see a roller bearing in the grank. I have no idea if it is correct or not.

How should I check it? Or should I just replace it?
Like everything else, pilot bushings/bearings can be done wrong. Roller bearings have in fact eaten the nose of $2500 ZF clutch input shafts. They are not repairable. The bearing (or bushing) must live in an extremely inhospitable area on the end of the crank, with intermittent high loads & vibration, no lube beyond whats there at installation, heat and abrasive debris from clutch disc wear.

With pilot bushings, there are THREE different Oilite materials possible at chain auto parts stores. Due to the cost of copper in recent years, some 'Oilite' has so much iron filings adulterating it, the 'bushings' are magnetic! Oilite SAE 841 is the good stuff; Super-Oilite (80% iron) and Super-Oilite 16 (79% iron & 1% graphite) will wear input shaft noses about as fast as a seized roller bearing; avoid them by carrying a magnet & checking before paying.

Lakewood Industries (Summit & Jegs) sells a good Oilite 841 bushing that fits ZF input shaft noses, but being intended for Chevy cranks is too small for the huge hole in a Cleveland crank. So I make a 3/4" thick aluminum adapter that press-fits in a 351-C crank and takes a Chev bushing. Been in our engine for over 10 years with zero problems.
quote:
Of coarse if you do not understand clearances and tolerances and it happens to fit loose and it works,
well I guess you have luck on your side.


DAMMIT--- I called in sick the day they were teaching bout them clearances and tolerances... I sure wish I understood more about those mysterious things. I guess I will just hope my luck holds out until I can get some schoolen on the clearances and tolerances thingies...

roll on floor
If a crankshaft journal can be welded for a repair, then there is NO reason a ZF input shaft couldn't also be welded for a repair.
Myself personally I ONLY use the bronze pilot bushing, it's material being the "Sacrifical Lamb". My piece of mind is WORTH the extra cost of the bronze bushing.
You guys must be on food stamps , that want to save a few $$$ for a questionable pilot bushing..Mark
(ZR1 Pantera)
Sarcasm
DAMMIT--- I called in sick the day they were teaching bout them clearances and tolerances... I sure wish I understood more about those mysterious things. I guess I will just hope my luck holds out until I can get some schoolen on the clearances and tolerances thingies...

Whelp, I guess I hit a nerve. If you need help with your Pantera their is a quality shop 15 min down the road in Lake Elsinore; Full Throttle Pantera,s run by Don Bryar's. he may be able to help you on such matters. He has some very nice and over the top Pantera's in his shop worth the trip.

Mark
quote:
Whelp, I guess I hit a nerve. If you need help with your Pantera their is a quality shop 15 min down the road in Lake Elsinore; Full Throttle Pantera,s run by Don Bryar's. he may be able to help you on such matters. He has some very nice and over the top Pantera's in his shop worth the trip.

Mark


Help for what? I was commenting on the bronze bushing, not asking for help on anything.

I an very familiar wil Don and Full Throttle Pantera's. In fact, he is one of my neighbors. I have also been to his shop. Yes, he does great work.

Did your post rub me wrong?, yep! Kind of condescending and making some assumptions about other peoples knowledge and skills. Since you don't really know me or my work background, to assume I don't know about "tolerances and clearances" is short sighted on your part. Then again, maybe I am just getting too sensitive in my old age.

Take care, Scott
Isn't this thread also a little bit about supporting and promoting those here who have gone out of their way to source, engineer, create and supply the best they can for the hobby? Like Marlin and Scott?

I wonder what Dorman would charge to tool up and supply the real bronze SAE oilite machined pilot bushing in the quantities we consume?

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