The Daughter’s ‘84

[ArdWrknTrk]

I need a little help determining what the rear axel is in the ‘84 F250. The axel code on the door sticker is 72. That code does not have a listing for 1984 in the rear axel documentation on this site.

The Dana BOM number from the axel tag says 605205-7. That code comes back to a 1983 to 1985 1/2 Dana 70 from a chassis cab F350. The truck is not a chassis cab. It is a pickup.

So you can see the issue? The two pieces of info seem to conflict.

Clear pic of the door tag???

Are you sure it's not code G2? Which would be a 4.10 LS Dana 70U (6,300#) in a pickup for '84-'85?

Code 72 seems correct for that same axle in an '85 Model Year according to Gary's list...

What is the wheel mounting width (track width) of the axle?

Chassis cab would have 34" wide spring perches and 2 1/2" wide pads for the springs.

Have the perches been re-welded?

I used to see more 70's in vans than in pickups. (but, again the frame widths are different)

D70 should have 3 1/2" tubes and 70 cast in the lower right quadrant web as shown in this illustration from the Spicer service & maintenance booklet.

 

[Gary Lewis]

Clear pic of the door tag???

Are you sure it's not code G2? Which would be a 4.10 LS Dana 70U (6,300#) in a pickup for '84-'85?

Code 72 seems correct for that same axle in an '85 Model Year according to Gary's list...

What is the wheel mounting width (track width) of the axle?

Chassis cab would have 34" wide spring perches and 2 1/2" wide pads for the springs.

Have the perches been re-welded?

I used to see more 70's in vans than in pickups. (but, again the frame widths are different)

D70 should have 3 1/2" tubes and 70 cast in the lower right quadrant web as shown in this illustration from the Spicer service & maintenance booklet.

The 605205-7 does decode to E4TA 4001-BEB or BEC with a 4.10 ratio in an 84 F250/350.

[ArdWrknTrk]

The 605205-7 does decode to E4TA 4001-BEB or BEC with a 4.10 ratio in an 84 F250/350.

Is one limited slip and the other is not?

Because it seems G2 is LS and code 72 is open.

[Gary Lewis]

Is one limited slip and the other is not?

Because it seems G2 is LS and code 72 is open.

Both show as open/unlocked:

[Gary Lewis]

Both show as open/unlocked:

And I should have posted this to complete the loop:

[Atlas75]

Clear pic of the door tag???

Are you sure it's not code G2? Which would be a 4.10 LS Dana 70U (6,300#) in a pickup for '84-'85?

Code 72 seems correct for that same axle in an '85 Model Year according to Gary's list...

What is the wheel mounting width (track width) of the axle?

Chassis cab would have 34" wide spring perches and 2 1/2" wide pads for the springs.

Have the perches been re-welded?

I used to see more 70's in vans than in pickups. (but, again the frame widths are different)

D70 should have 3 1/2" tubes and 70 cast in the lower right quadrant web as shown in this illustration from the Spicer service & maintenance booklet.

Here is the door tag. Even though it seems like we solved the issue. Dana 70 it is!

[Gary Lewis]

Here is the door tag. Even though it seems like we solved the issue. Dana 70 it is!

Looks like "72" to me.

So we have another instance of one part of the MPC being wrong. As shown below it says that an 84 didn't get that axle. But here's a truck made in January of 84 that got one.

Glad you had the BOM so we could look it up another way.

[Atlas75]

Looks like "72" to me.

So we have another instance of one part of the MPC being wrong. As shown below it says that an 84 didn't get that axle. But here's a truck made in January of 84 that got one.

Glad you had the BOM so we could look it up another way.

I haven't posted in a while but my daughter has been enjoying her truck. So far we have upgraded the stereo and done a few things to the glow plug system. We still have more to do with the glow plug system as we attempt an upgrade to the 7.3 controller. More on that at another time.

My question for today involves the clutch. My daughter drove to work yesterday and everything was fine. On the way home however, the clutch pedal would only return half way. If she didn't use it for a bit, it would slowly return to the resting position. I haven't had a chance to crawl under the truck yet but this sounds like it could be the slave cylinder. Anything else I should be looking for?

[ArdWrknTrk]

I haven't posted in a while but my daughter has been enjoying her truck. So far we have upgraded the stereo and done a few things to the glow plug system. We still have more to do with the glow plug system as we attempt an upgrade to the 7.3 controller. More on that at another time.

My question for today involves the clutch. My daughter drove to work yesterday and everything was fine. On the way home however, the clutch pedal would only return half way. If she didn't use it for a bit, it would slowly return to the resting position. I haven't had a chance to crawl under the truck yet but this sounds like it could be the slave cylinder. Anything else I should be looking for?

I don't think the slave cylinder is going to magically suck fluid back in, but at least it's external and you can pull back the rubber boot and look for fluid.

Has the level in the master gone down? (don't forget the rubber boot sometimes sticks and makes it appear dry)

I'd be looking at the 4 fingered bushing that connects the pedal arm to the master pushrod eye.

When that bush wears through you get poor adjustment and eventually the eye wears a groove in the pin of the arm.

When that happens replacing the bush results in a crunch and immediate failure.

In an emergency I temporarily fixed this by JB Welding a 9mm casing over the pin and using a washer & circlip in the extractor groove.

Also look at the plastic bushings where the pedal crossover shaft pass through the support casting.

I've never encountered it myself, but pictures on the forums leave no doubt that it happens.

If the slave proves good, these are a good place to start.

Basically you want to remove as much linkage slop as possible without preloading the master to the point where it closes off the reservoir.

This is just my experience, and others may have more to add.

 

[Atlas75]

I don't think the slave cylinder is going to magically suck fluid back in, but at least it's external and you can pull back the rubber boot and look for fluid.

Has the level in the master gone down? (don't forget the rubber boot sometimes sticks and makes it appear dry)

I'd be looking at the 4 fingered bushing that connects the pedal arm to the master pushrod eye.

When that bush wears through you get poor adjustment and eventually the eye wears a groove in the pin of the arm.

When that happens replacing the bush results in a crunch and immediate failure.

In an emergency I temporarily fixed this by JB Welding a 9mm casing over the pin and using a washer & circlip in the extractor groove.

Also look at the plastic bushings where the pedal crossover shaft pass through the support casting.

I've never encountered it myself, but pictures on the forums leave no doubt that it happens.

If the slave proves good, these are a good place to start.

Basically you want to remove as much linkage slop as possible without preloading the master to the point where it closes off the reservoir.

This is just my experience, and others may have more to add.

I checked the slave cylinder and it appears to be dry. I'm not sure why, but I never checked the clutch master cylinder fluid level when we bought the truck. It was quite low so I topped it off. I also noticed that the seal/boot under the cap was really distorted. I don't think it was making a seal between the master and the cap. I wonder if the fluid evaporated slowly over time? I tried the clutch both with the engine running and with it off. It seems to be functioning as it should now that the fluid level is good. I'll try to take it for a drive tomorrow and see what it does.