E4OD front pump bushing size and machining

[1994Diesel]

I have a new bushing which has an O.D. of 2.109" and the bushing bore is also 2.109". To snug of a fit I think. I have read on other forums that the bore should be machined/ honed out to 2.123 - 2.125". This would make the bore larger than the bushing O.D. which sounds like a recipe for another bushing walking out of the bore.

What should I shoot for here as far as the bore size. I don't want to have to pull this transmission again.

Thanks for the help.

 

[1994Diesel]

I'll re-measure everything tomorrow to double check. On second thought, one would think that a bit of interference fit would be desired for a bushing maybe?

 

[rdoimages]

Freeze it and go with it?


89 F-350 sc 2wd DRW 7.3 ATS 088, C-6 with Gear Vendor and a rats nest of wiring that was free with purchase.
00 Excursion limited, 6.8 4x4
2001 Jeep Cherokee Classic Sport 4x4 4.0 auto

 

[1994Diesel]

I just thought it was unusual since I've read that all aftermarket bushings are oversized.

 

[typ4]

You can get os bushings, not all are

 

[1994Diesel]

You can get os bushings, not all are

Gotcha. That's what I was beginning to think. I just wanted to double check before I put this transmission back in the truck.

 

[trackspeeder]

Freeze it and go with it?


89 F-350 sc 2wd DRW 7.3 ATS 088, C-6 with Gear Vendor and a rats nest of wiring that was free with purchase.
00 Excursion limited, 6.8 4x4
2001 Jeep Cherokee Classic Sport 4x4 4.0 auto

What he said.

 

[1994Diesel]

I just installed the bushing. I found that I have about .008" hub to bushing clearance. I can not find a spec anywhere for hub to bushing clearance but I am assuming that is acceptable. When staking the bushing I caused a crack in the bronze around the area that was staked. It looks superficial and lower than the surface that would contact the hub.

 

[FORDF250HDXLT]

aftermarket bushings are larger because if a bushing needs to be replaced in a pump,then odds are it spun and or walked forward.if you could find an oem bushing and tried pressing it in the pump where a bushing walked,then odds are that bushing would walk in the sloppy hole too.

if you don't ream out the bore for the oversized/replacement bushing,then you'll risk the bushing seam splitting and coming undone.once this happens the seam edge/lip wont be smooth which is no good and the converter will lock onto the bushing and spin it inside the pump.then you'll be doing the work all over again until you do it correctly.

i've earned this shameful t-shirt myself. trust me.you want to follow the instructions with the bushing.you can even make it better.see the tech section for the shift kit and pump mods for full instructions.
you can vary from those instructions if you want.............but don't say i didn't warn ya lol.

 

[1994Diesel]

My issue with the whole process was if the bushing O.D. is 2.109" and then the recommended bore size for and overzized is 2.123 - 2.125", that makes the bore 0.014 - 0.016" to large for the bushing. I think I have an "OE" sized bushing and still have plenty of room to play with on the bushing bore. Its just bizarre to me that there is not very much info out there about bushing clearances. I've been hitting the googles hahaha.

 

[1994Diesel]

Just found some literature. Its very general, not specifying any make or model, but it is speaking of bushings in automatic transmissions.
It states that: "If you want to measure bushing clearance to, use the rule of thumb that anything over 0.006 in. is excessive."

According to that I have excessive clearance.

I feel like doing this whole project over with the superior brand bushing that has the kurled bushing and sending the pump out to a shop to have it machined.

 

[1994Diesel]

aftermarket bushings are larger because if a bushing needs to be replaced in a pump,then odds are it spun and or walked forward.if you could find an oem bushing and tried pressing it in the pump where a bushing walked,then odds are that bushing would walk in the sloppy hole too.

if you don't ream out the bore for the oversized/replacement bushing,then you'll risk the bushing seam splitting and coming undone.once this happens the seam edge/lip wont be smooth which is no good and the converter will lock onto the bushing and spin it inside the pump.then you'll be doing the work all over again until you do it correctly.

i've earned this shameful t-shirt myself. trust me.you want to follow the instructions with the bushing.you can even make it better.see the tech section for the shift kit and pump mods for full instructions.
you can vary from those instructions if you want.............but don't say i didn't warn ya lol.

How did you hone out your pump with out flaring out the edges with the engine hone? I have 2 - 7 in hone, but the hone blocks are long enough to where the are hard to keep flat in the bore. Thanks

 

[OLDBULL8]

Me thinks your making a mountain out of a mole hill.

Size to size is called an interference fit. That's why the replacement bushing is that way, it's staked in two places (notches for staking) so it can't turn. If the bushing would be a .001+ OS, then it would be a press fit, and the bushing shaft bore would have to be honed or machined to fit the shaft.

I'm sure you just can't push the bushing in without some force. Freezing it and dropping it in is the normal method of installation for a size to size fit.

If shaft is worn to an extent that the clearance exceeds the tolerance, then the shaft should be changed.

 

[1994Diesel]

Me thinks your making a mountain out of a mole hill.

Size to size is called an interference fit. That's why the replacement bushing is that way, it's staked in two places (notches for staking) so it can't turn. If the bushing would be a .001+ OS, then it would be a press fit, and the bushing shaft bore would have to be honed or machined to fit the shaft.

I'm sure you just can't push the bushing in without some force. Freezing it and dropping it in is the normal method of installation for a size to size fit.

If shaft is worn to an extent that the clearance exceeds the tolerance, then the shaft should be changed.

Thanks Bill, You are right. I am just anxious about spinning another bushing.

 

[trackspeeder]

Once the bushing is staked it wont spin.