E40OD question

yes,

Yep. It do. It's big, heavy and expensive. It will shudder after a while if the fluid is not regularly changed just like most other Ford auto boxes of the era. It is also a real 4 speed unit. It has a band in it but, the band is only used for manual second selection. Everything else is clutches including non-manually selected second. The clutches are it's big advantage over the AOD or AOD-E units since they use a band for OD. That is usually the first thing to give when towing.

Lugnut

The reason the AOD was a poor tower is not because of clutch design but rather that it was made for max MPG and cannot use torque converter multilication in 3rd and 4th by design and is ALWAYS in a lock up mode in those gears. It was on of those things that looked good on papaer but do not play out as planned in the field.

----------------- TheSnoMan.com

If the AOD unlocked and used torque multiplication, the band would just fail quicker. Also, IIRC, the AOD does not use a lockup converter but an inner shaft such that "unlocking" is not possible w/o actually downshifting. The AOD-E does use a locking converter that can be controlled via the solenoid allowing it to unlock. The E4OD has a locking converter and may unlock in any position. The programming in the later units was such that it may lock as early as second gear and stay locked during all subsequent upshifts which tends to kill torque. I installed an Interceptor in mine which allows it to unlock during each shift and delay lockup allowing better performance during upshifts. It also provides quicker unlocks and downshifts for better acceleration and pull when the throttle is opened quickly such as when passing on 2 lane roads. I have also done other mods and updates to mine when I rebuilt it which makes it shift and perform almost as well as a decent C6.

Lugnut

The reason the AOD was a poor tower is because of the small OD clutch pack. At only about 4.5 inches across, they had a tendency to weld themselves together during their "hunting" sessions. Seen it hundreds of times.

Maybe but the point is that it was never designed to handle a lot of torque from converter in upper gears so it was not to generous. Also, I know that there is not clutch in its converter but it is simpler to say it locks up. THis is not a new idea. GM did it with Hydromatics starting in 1939 when they came out. They used a fluid coupling of sorts at stall with no torque multiplcation in first and reverse so to speak and "locked up" in upper gears. They did this through Roto Hydromatic which was last made in 64

----------------- TheSnoMan.com

In stock form, you are correct about the clutch. My experience has been that the OD band is the weak point in the AOD. Built right, that can be prevented. But, based on my experience with one in a Bronco powered by a 14# puffed

5.0L, I can stop the hunting, welding and band failure with enough pressure, wide band and huge servo. What we have not figured out is whether or not Art Carr can make a strong enough input shaft to resist twisting when towing on boost. We have had that happen twice.

The E4OD properly built can handle the torque of any of the stock engines but, as in any OD - or other trans - it should be manually downshifted or deselect OD if it is hunting under the prevailing operating conditions. It will only build heat on the clutches when locking or unlocking. The converter will generate heat any time it is unlocked and "slipping". I do not use "slipping" to mean the converter clutch or converter is malfunctioning - simply not running at 1:1.

In any case, the E4OD as bad as the early ones were before being rebuilt to the late specs was still superior to any of the other boxes available for towing or other heavy work. Without the OD part of it, the higher speeds limits beginning in that time period would have been unattailable for sustained periods with decent fuel economy. I suppose they could have used taller rear ratios to cruise faster but, pulling power in a truck would have been in the toilet.

Lugnut

Lugnut,

I have a 95 Bronco with the E4OD and often saw this line repeated when I first researched it 6 months ago. Would I be correct in assuming that my E4OD has all the updates that are available? What is the track record of the last years of the E4OD? I hear it's better, but not exactly how good. Mine just turned over 100K and I don't tow so I am hoping it will outlast the body. That shouldn't be too tough for a Ford truck :).

Calvin

The '95 already had the most critical updates done. There were tweaks right up thru the '97 model including changing the pump from 5 to 7 lobes to increase delivery and reduce noise. In '98 or so it was updated and the torque capacity increased along with the model designation to the 4R100 which has continued to develop. My '93 went down about 138K after towing an 11k outfit 4 round trips in the mountains. Even then, it was the torque converter started slipping and shuddering. The rest of the trans was like new. I went ahead and did all of the updates and beefed it with a forward clutch pack from a diesel unit stuffed full of plates and a couple of other items, and installed a shift kit. Last year if was pulled to replace the rear crank seal and I installed a seal kit at 220K just because it was already there and easy to do at the time. We have a '94 Bronco with the 5.8L and E4OD with just over 160K with no problems. It has been used for a few cross country tows weing in around 6K. It has always had a hude cooler installed and regular service. It also has a minor upgrade shift kit installed to give it a little pressure boost.

Service is the life of the later units. It should be done every 25-30k miles without fail. More critical - more often if you tow.

BTW, if you have not already had to replace the strut bushings, you can greatly improve the driving and tighten up the steering with urathane bushings. I couldn't believe the difference when we installed them the first time. Well worth the couple of extra bucks. Imention this because yours are probably well overdue especially on the right side if you have not already had the replaced. Ever notice it dart a little when you hit a pothole or hit the brakes?

Cheers Lugnut

That's good to hear. I did a complete purge and filter change at 100K but I am not sure what it saw before under the P.O.s. I plan to put a drain plug on it at 125K.

By struts do you mean the radius arms? I had to replace the drivers side bracket and bushings at 95K because the P.O. let it go so long. He thought the knocking noise was a bad CV joint. I guess the whole RWD concept was lost on him >:(. The passenger side still seems to be serviceable and I have no interst and tearing into that beast just to have a look. And yes, that bushing does make the TTB Watusi even worse than usual.

Calvin

Radius arm is what Ford calls them I use the terms interchangeable simply because so many around here have no idea what a radius arm may be. Unless they are really bad, having a look doesn't do much. They make noise and degrade steering/drive quality long before you can "see" a problem. Another problem to watch in that Bronco is a thump under the floor after you stop moderately and release the brake to start again. That is usually the drive shafe slip joint at the rear of the trans. Usual fix is remove drive shaft and lube splines with EP grease.

Lugnut

I have a bit of that; do you mean the spline in the middle of the driveshaft with the grease fitting or the actual slip yoke?

Also, what's your opinion of polyurethane strut rod/axle pivot bushings? Worthwhile upgrade, or no? Seem to be about the same price as rubber and at some point I will probably want to replace them.

nate

The slip joint which is a problem is the one in the rear of the transmission. The center joint has a zerk fitting from the factory. might want to check the rubber bushing around the center bearing to be sure it remains intact.

It is my opinion that the polyurethane bushings are the only way to go. I would not replace still good factory bushings but replacements are well worth the small extra expense. The polyurethane bushings dramatically tightened his hearing and improve driving quality over worn factory bushings. be advised that the polyurethane bushings will transmit slightly more road noise and harshness.

Cheers

Lugnut