Rebuilding An Indestructible Tranny-The 833

This isn't mine. I found (stole) it from here, and thought you'd like to see.

~Jason


Rebuilding the A-833 Four-Speed Tranny - Gear Grabbin'
Rebuilding An Indestructible Tranny-The 833
From the March, 2004 issue of Mopar Muscle
By Randy Bolig
Photography by Jamie Passon
http://www.moparmusclemagazine.com/..._four_speed_tranny/viewall.html#ixzz2KivR2THr



You're cruising around in your Mopar, and your four-speed is making a little noise. Is it shot? do you need to buy another one? Thankfully, the 833 is virtually an indestructible tranny and can be rebuilt with a little time and patience. With the help of Passon Performance in Sugarloaf, Pennsylvania, we will try to show you as in-depth an article on rebuilding a tranny as you have ever seen. Luckily, most of the parts for these transmissions are still available, so unless you have a major internal meltdown, a rebuild is an option. Be advised, many "parts house" replacement parts for these transmissions are slightly incorrect. This is especially true of the 308 bearing and early synchronizer rings.


The A-833 four-speed was built by New Process. produced from 1964 until 1987, it is most noted for its strength and durability. From 1964 until 1972, it was built in two configurations-a 23-spline input shaft and an 18-spline input shaft. These shafts are not interchangeable alone, and the entire gearset is matched and must be changed as a complete assembly. Typically, the 23-spline units were installed in small-block cars and wedge-headed big-block cars up to 426 ci in 1965. Later, the 383 and 400ci engines received the 23-spline tranny. The 18-spline unit, popularly known as the "Hemi" four-speed, was used in cars equipped with a 440ci engine from 1966 to 1972 and in the famous 426 Hemi engine from 1964 to 1971. After 1972, the 1:1 final-drive-ratio gearset was made for another two years, bringing its production run to an end in 1974. However, there was an overdrive unit that was made from the early '70s until 1987. This had a final drive of .73:1. During the early years of this run, it was mainly placed in A- and F-Body cars (Darts, Dusters, and Aspens/Volares). The later years of this production run were placed in half-ton Dodge trucks. Over the years, there were several different designs of internal parts. An example of this would be the synchronizers. There are also several different case configurations and gearsets.


Walk up to a pile of A-833s at a swap meet, and the most obvious differences are their overall length and output shafts. Early trannies feature a flanged yoke connecting to the driveshaft, and later models had a slip-yoke. Chrysler made two different length A-833s over the years, and while the main gear housings were sized the same-and for the most part were the same casting for most models-the tailshaft housing differed. A- and F-Bodied cars received the shorter output shaft and housings; B-, C-, and E-Bodies received longer tailshafts. The flanged ball-and-trunion output shaft was used in 1964 and 1965. In 1966, the slip-yoke output replaced the ball-and-trunion on all A-833s. But enough with the history lesson, let's get dirty.

 

These are the parts needed for a quality rebuild. (Passon Performance can supply all these parts, plus anything else you may need along the way.) Simply taking the tranny apart, cleaning everything, and reassembling it won't solve any issues. These parts are a must for a tranny rebuild that will last a long time.

 

When removing the bolts on the side cover, keep in mind there are two different styles of shoulder bolts used in cases that are post-1967.

 

After the cover is removed, remove the brass shifter forks (later models had steel forks), and make sure the reverse arm is forward (hook-shaped arm).

 

http://image.moparmusclemagazine.com/f/31801560/mopp_0403_06_z+rebuild_833_tranny+remove_bolts.jpg



Remove the four front-bearing-retainer bolts and the six tailhousing bolts.

 

With the bolts removed, pull the tailshaft housing away from the main case. The output shaft and the gears will come with it. There are 16 rollers that surround the front end of the shaft assembly. They will fall out when the assembly is removed. that's ok, since they will be replaced. just make sure all are accounted for, so they don't end up making their way back into a freshly rebuilt unit.

 

With the shaft assembly on the bench, remove the brass synchro ring and the snap-ring that retains the 3/4 gear synchronizer-assembly.

 

If you have an A-Body, a pre-'70 B-Body 23-spline trans, or a '66-'67 18-spline, the rear bearing is a 307, and the snap-ring needs to be squeezed together to remove the shaft. The '70-and-up B- and E-Body trannies, and 'the '68-and-up 18-spline trannies have the 308 rear bearing. the snap-ring needs to be expanded to remove the shaft.

 

After tapping the end of the output shaft into the tailhousing and removing the assembly, expand and remove the snap-ring near the speedometer gearing that holds the main-shaft bearing in place.

 

With the snap-ring removed, press the bearing from the shaft.

 

With the bearing removed, remove first gear. Next, remove the snap-ring behind the synchro-hub, and then remove the synchro assembly. Finally, remove second gear.

 

Remove the snap-ring that holds the input bearing in place.

 

The counter shaft needs to be driven from the front of the case, out the back. There is a small half-moon key that will fall out, (this will be replaced as well), however, make sure it is accounted for. Once this is done, the cluster gear will drop to the bottom of the case. We will be replacing the 76 rollers inside the cluster gear, so make sure they are all out of the case.

 

Remove the input shaft from the case by tapping it into the case with a brass (not steel) hammer. Then press the input bearing from the shaft.

 

The detent mechanism for reverse is located on the rear of the case and needs to be removed.

 

You need to press the reverse idler shaft out of the case. A little ingenuity and a C-clamp works here. When the shaft is out, remove the reverse arm. Now thoroughly clean all the parts and the case. Inspect all the gears, sliders, forks, hubs, keys, and shafts for excessive wear and damage. Check synchro teeth points and sides for rounding. Synchronizer assemblies should be disassembled, cleaned, and inspected as well. These should be kept separate, as the parts are similar but not identical, and could get mixed up. The strut key springs should be offset when reassembled, not installed into the hubs oriented identically to each other. Damage to the strut keys and other components will occur if they are installed incorrectly.

 

Sand the synchronizer cones on each gear with 120-grit paper to remove any glazing that has occurred, and then thoroughly clean them. Check gear cones for wear. This is done by installing a new brass synchro-ring onto the gear and trying to turn the gear while applying slight down-pressure. If the ring grabs the gear and forces it to turn as well, the gear is in good shape. Grease all the bores in the gears. install second gear, the brass synchro-ring, and then the 1/2 gear synchro-assembly. Be sure to index the synchro ring to fit properly against the hub. It may sound confusing, but it is simply a reverse assembly from when you disassembled the shaft.

 

Install the snap-ring to hold this portion of the shaft assembly in place.

 

Install third gear, the accompanying synchronizer ring, and the 3/4 gear synchronizer. install the snap-ring to hold it in place. Again, be sure to install the synchronizer ring properly so the ring indexes the hub correctly.

 

On applications using a 307 bearing, put the large snap-ring on the shaft, then press the rear bearing onto the shaft. On the backside of the bearing, there is a groove for a snap-ring in the shaft. Use the thickest snap-ring possible; this is necessary for proper bearing endplay. (These are included in the rebuild kit from Passon.)

 

Before reassembling the tailhousing assembly, make sure you clean the housing and install a new tail bushing and seal. Press out the old bushing and install a new one. The oiling hole in the bushing should be located at the 4 o'clock position to line up with the oil channel in the housing.

 

When installing the shaft into the tailhousing, the large snap-ring needs to be either expanded or contracted (depending on the bearing size). slid the assembly into the housing until the bearing bottoms out. Release the snap-ring into its groove.

 

Press the front bearing onto the input shaft, and install the snap-ring in place. Again, use the thickest snap-ring that will fit to give you the proper bearing endplay.

 

Pack the cluster bore, rollers, and spacers with heavy grease. The large tube sits in the center of the bore, and then two rows of 19 rollers and spacers are installed. The order of assembly consists of 19 rollers, then a spacer, then 19 more rollers, and another spacer on each side. Assembly is aided with the use of a dummy shaft.

 

Install the two thrust-washers copper-side in, one on each side of the cluster gear assembly. Orient the tangs up and down for installation, and hold them in place with grease.

 

Set the cluster assembly in the housing, allowing it to rest in the bottom of the case. install the input shaft.

 

Lift the cluster assembly so it meshes with the input shaft. Now the counter shaft can be installed, and it pushes the dummy shaft out of the case. Don't forget the half-moon key goes toward the back of the case. With the shaft installed, cluster gear endplay should be between .016 and .025 inch. If you have more, check the case and the face of the gear for wear, and replace as necessary.

 

Install a new o-ring on the reverse arm, and then put the arm into the case. Now, install the pin, reverse idler gear, and shaft with half-moon key. Make sure it all works smoothly. The idler gear points should face the rear of the case.

 

Put some grease in the input shaft, and install the new set of 16 rollers.

 

When you are installing the tail assembly into the main case, be sure not to knock any of the 16 input rollers out of place. Turning the input shaft helps prevent this. Make sure the brass synchro-ring is indexed properly with the synchro hub before the case is bolted to the tailhousing; otherwise, the shaft will bind. When you finally get the tail assembly into the case, snugly install two tail housing bolts, and make sure all the synchronizers and gears operate smoothly. If everything is fine, install the rest of the bolts and tighten to 50 lb-ft.