New Diff Fitment Issues

[TWebb]

Good day.

Just completed preparing a new diff with mag carrier and aluminum nose. Attempted to install but could not get the new unit to fit into the car.

Pulled the old diff unit out of storage to see if I could reinstall the old unit. No issues. Popped in without an issue.

Tried the new unit again with no luck.

Has anyone had similar issues?

Stumped.

[promotor]

Good day.

Just completed preparing a new diff with mag carrier and aluminum nose. Attempted to install but could not get the new unit to fit into the car.

Pulled the old diff unit out of storage to see if I could reinstall the old unit. No issues. Popped in without an issue.

Tried the new unit again with no luck.

Has anyone had similar issues?

Stumped.

Do you have any photos of the new diff / final drive assembly? Some aluminium noses are reproductions of the Escort type nose so are bulkier than the original Elan type which is Anglia 105e derived. Perhaps that is some of the issue?

[TWebb]

I will upload a couple photos.

I'm hoping these are the correct components given I bought everything from from TTR.

Photos to come

[baileyman]

After cutting back the lower corner on my TTR diff nose it slipped right in. John

[661]

Is it the gap between the top and bottom of the chassis that won't fit or the distance between the carrier bolts?
TTR stuff is beautifully manufactured not to fit! It usually requires a fettle. Mine didn't as I have a 'high back' chassis.
Is the rear wishbone off entirely?

[TWebb]

It appears the fitment issue, or lack there of, is due to the extra "meat" around the top mounting holes (I'm calling them the ears) of the magnesium diff carrier. I presume the extra material, when compared to the original, is to provide extra strength. A quick measurement indicates approximately 1/8" off additional material.

I presume I can grind down the diff carrier in this location. Not something I want to do to a brand new carrier.

There is no suspension on the car at this point. I am replacing the rear uprights. Found an issue with these as well, but it should be an easy fix. Ordered AN bolts to use on attaching the rear uprights to the A-arms. Old uprights used 7/16 bolts. I ordered 7/16 AN bolts, but unfortunately the shoulder on the AN bolts are too large for the holes drilled in the uprights.

Not a big deal, but a pain.

[661]

Are you using a diff brace as well? That may need to go on once the diff has been placed in it's hole. (awkward, I know)

[512BB]

'It appears the fitment issue, or lack there of, is due to the extra "meat" around the top mounting holes (I'm calling them the ears) of the magnesium diff carrier. I presume the extra material, when compared to the original, is to provide extra strength. A quick measurement indicates approximately 1/8" off additional material.

I presume I can grind down the diff carrier in this location. Not something I want to do to a brand new carrier. '

I have had this problem more than once when fitting diffs back into a chassis. If I am fitting a diff that has the very squared off front iron housing, out comes the angle grinder, to remove A LOT of metal, and to shape it into a curve at the front, like some iron housings are to start with. You have to be careful not to go to mad, or you could go into the oil channel that runs from front to back. A lick of paint afterwards, and you are good to go.

Next, on occasion, I have taken the angle grinder to the lower most point on the curvature of the iron housing and ali carrier. Just taking off a mil or two in that area can make the job of refitting the diff so much easier, and in they pop.

Lastly, as you say, I have in the past shaved the sharpe 90 degree edge of the offending ear, and in it went. Dont forget to add a stainless steel penny washer to the underside of both ears. There is a reccess for that purpose, to spread the load, and put plenty of anti seize on the bolt that you fit from the top, not the bottom.

I am sure you realize, diffs wont go in with a diff brace fitted before fitting the diff to the chassis.

Good luck,

Leslie

[TWebb]

Thanks all. Good to know that others have run into the same issue.

Yes. I will be using a diff brace. It will be fit once the diff is in its proper location.

[prezoom]

Not stated, but if you are using AN bolts, you will need to use the corresponding size AN special washer beneath the bolt head.

[2cams70]

There’s actually 4 different types of English Ford differential carriers as far as I know:

1. The Anglia / Mk1 Cortina one
2. The Mk2 Cortina / Capri one
3. The Mk1 Escort one (up to around 1974)
4. The Mk2 Escort one (post 1974)

All have subtle differences in the casting. Both Escort types have the lower squared off part at the bottom of the front of the nose. The MK2 type has substantially beefed up ribbing.

[TWebb]

AN Bolts:

Rob,

I always use AN washers with AN bolts. Thanks

[2cams70]

Some of those "AN" bolts have a lower tensile strength than SAE bolts. It's the grade of bolt and it's tensile strength that's important and not whether it's to the SAE standard or the AN standard.

[TWebb]

Tensile Strength:

Roger that

[Foxie]

<Snip>
I have had this problem more than once when fitting diffs back into a chassis. If I am fitting a diff that has the very squared off front iron housing, out comes the angle grinder, to remove A LOT of metal, and to shape it into a curve at the front, like some iron housings are to start with. You have to be careful not to go to mad, or you could go into the oil channel that runs from front to back. A lick of paint afterwards, and you are good to go.
<Snip>
Next, on occasion, I have taken the angle grinder to the lower most point on the curvature of the iron housing and ali carrier. Just taking off a mil or two in that area can make the job of refitting the diff so much easier, and in they pop.

I am sure you realize, diffs wont go in with a diff brace fitted before fitting the diff to the chassis.

Leslie

I can second the use of the angle grinder, as above.

My diff goes in no problem with the substantial brace already bolted on.