Ford E4OD Overhaul for Heavy Duty Towing and Off-Road Use

FSB Rebirth: Part 2- E4OD Overhaul

Bruce W. SmithPhotographer, Writer

Refurbishing a worn 4x4 that’s been sitting outdoors neglected for years isn’t an easy process. In our first installment we noted our 25-year-old full-size Bronco, affectionately called Eddie, was starting to show the ominous signs of transmission failure along with a 5.0L EFI that’d seen its last days.

We pulled the old engine and replaced with with a reman upgraded with a few moderate performance upgrades. Now that the engine is back in its cradle, we turn our attention to the next component along the powertrain line: The E4OD.

Eddie’s E4OD’s shifts were getting lazier and lazier as the weeks went by prior to the engine taking a dump, and the transmission felt sluggish pulling away from a stop or climbing steep grades. The transmission fluid was also closer to brown than red, with the faint odor of burned clutch.

GEEZERS ARE COOL

When the engine was out we figured it was the perfect time to pull the tranny so it could be put in the hands of a professional rebuilder to diagnose and remedy the somewhat obvious internal issues. We didn’t have to go far to get the help, either.

A few miles from our office is a little shop out in the country that has more than 80 years experience rebuilding automatics between the owner and his head bench wrench. Gary Haslip’s Geezer Garage in the northern outskirts of Eugene, Oregon, is the best kept transmission secret in the Pacific Northwest. He likes it that way.

Gary, and his ace rebuilder, Phil Mitchell, have been overhauling automatics for 40 years, most of that time working for AAMCO. The two techs estimate they have rebuilt more than 1,500 E4ODs, and even after “retirement” from the corporate transmission world several years ago, they continue to add to that number as Ford truck automatics continue to come in the Geezer Garage doors.

Phil estimates he alone has rebuilt more than a 1,000 of Ford’s truck automatics since they were introduced in F-150/250s and Broncos in 1989. So we knew we were in good hands when we unloaded our greasy transmission on his workbench.

It took Phil less than 15 minutes to have the case gutted, the array of gears, clutches, steels, cases, planetaries, snap rings, valve bodies and shafts laying in a heap on the metal workbench. His diagnosis: Death by neglect.

It appears whomever the previous owners were never bothered to have it serviced since the day it left the dealer. Now, after some 220,000 miles, it was one off-road foray away from self-destructing. Our timing for having it rebuilt was perfect.

REBUILDING FOR DURABILITY

Ford’s E4ODs saw a lot of changes over the years, especially after 1994 and all the way into mid-1997 when Ford replaced it with the 4R100. (The 4R100 shares a lot of internal componants with the ’97 E4OD.) So our early model could be easily updated – and it could also be upgraded with many of the heavier-duty internals used in the Super Duty Power Stroke E4ODs of the era.

Gary contacted his two primary parts suppiers to get their take on the best route to take for a daily-driven street/off-road 4x4 E4OD rebuild. Jerry Clopton, the owner of Perfection Plus Transmissions in Portland, Oregon, suggested using a mix of like-new used ’97 Power Stroke E4OD and ’98 4R100 components to replace some of the weaker components in the ’89-‘95 F-150/Bronco transmissions.

In addition to stouter internal hard parts, Gary ordered up high-performance Alto PowerPacks from the Portland branch of Transtar Industries, a major suppier of transmission parts world-wide, so we could upgrade the clutches with Red Eagle frictions and Kolene steels, along with a TransGo “Tugger” reprogramming kit.

The end goal building our psuedo-hybrid E4OD was shaping up. The overhaul would accomplish the following: 1) maximize durability; 2) minimize internal heat build-up; and 3) increase the crispness of overall power delivery on road and off. What we ended up with is essentially a ’97 Super Duty E4OD in an F-150/Bronco case.

It took Phil about six hours to handle our E4OD heavy-duty overhaul. Gary says the cost of such a rebuild would typically run between $1,800-$2,800 depending on the performance level of the rebuild, the year, and condition of the original parts.

He also recommends using Mercon/Dextron III ATF and a torque converter matched to the engine and vehicle use. We slipped in a TCI Staurday Night Special Maximizer TC, setup with a 1,800-2,200rpm stall to match Eddie’s warmed up 5.0L EFI. A little muscle work under the truck and some 17 quarts of ATF later we headed out on our first test drive.

What a difference a performance transmission and properly matched torque converter makes! Our truck’s E4OD shifted faster, with a nice crispness. The big Bronco pulled hard off the line, snicked up through the gears and settled in with a little bump into overdrive when it hit highway speed.

Downshifts are also quick and firm, and in Low range the feel of power is even more impressive – even for a little 302. Eddie-The-Bronco has never felt better—and neither have we.

(Editor’s note: Next month we tackle the rust cancer around the rear fenders, and wrap our Bronco with new look. Stay tuned!)

TEN E4OD REBUILD TIPS

Upgrades/updates to beef up your truck’s Ford E4OD automatic to handle the rigors of engine mods and off-road use. Tips courtesy of Gary Haslip, Geezer Garage:
Rear planetary. Keep the three-pinion OE aluminum one if it doesn’t show signs of wear. This planetary seldom causes issues. If in doubt, replace it with a six-pinion steel version used in the Power Strokes.
Low Reverse Clutch. When installing the Low reverse frictions make sure the clearance is between .020-.040” to shorten the delay going into reverse. You can use perfromnace frictions and steels to get the tighter tolerances.
Center support. If it has a little bronze bushing (Pre-‘95). Toss it. Upgrade to the bearing version (’95 E4OD and 4R100). While the center support is out, add a gasket available from Sonnax #36743G.
Front planetary. Change from OE three-pinion aluminum to a six-pinion steel used in the Power Strokes because the splines in the aluminum planet strips.
Intermediate Clutch: Replace the two OE frictions and steels with three Red Eagle frictions and Kolene steels.
Overdrive planetary. Change the overdrive planetary to steel. This is a must as the aluminum versions had a tendency to split the neck.
Center Support Hub: Install a ’96-4R100 version that uses the roller bearing assembly instead of a bronze bushing found in’95-older E4ODs. Requires newer Center Shaft, too.
Pump. Nix the E9 (’89-’94) for an F5 (’95) or F8 (’98 E4OD) to provide better cooling and higher line pressures.
Servo piston. Replace the OE servo piston if it has the snap-ring and plate for a ’96-’97 style that’s sans snap-ring/plate.
Bearings and bushings. Replace all bearings and replace brass bushings that show wear.
Note: If this is your first E4OD rebuild rodeo, get an Automatic Transmission Service Group (ATSG) Ford manual and the companion “Update Handbook,” which covers the numerous upgrades made between 1989-1997.

SOURCES

Geezer Garage
541.554.0838

Perfection Plus Transmission
503.286.5550

Transtar Industries
800.345.7500
www.transtar1.com