Getrag rebuild / review

[EZGZ]

Had a couple guys as me for a copy of this recently so thought I would repost for those that didn't catch it the last time.

Enjoy!

GETRAG 360. 071. 4



Transfer case removal--

Disconnect wiring from switches on the transfer case and transmission

Disconnect front and rear driveshafts after marking with a punch/chisel for reinstallation later.

Remove transfer case shifter/bracket to enable removal of transmission adapter bolt to trans case.

Remove transfer case from transmission adapter--6 studs and nuts(13mm or 1/2")--the fluid does not have to be drained unless it is to be changed--no more than 30,000 miles if frequently pulling 10K or more.



To remove transmission, the boots and shifter must be removed. Check boot for leaks.

To remove the shifter from the top of transmission, remove snap ring located in the shifter 'snout', while pushing down on the shifter. Shifter lever may then be removed and set aside.

Remove wiring harness from clips on top of the transmission.

Support transmission with floor jack while removing crossmember and bolts in bell housing.

With additional jack supporting rear of engine allow engine and transmission to tilt rearward to allow the transmission top to clear the floorpan while simultaneously lowering and pulling the transmission away from engine. The transmission must stay in alignment with the engine while being removed and not put a load on the clutch disc hub.

After input shaft has cleared bell housing, transmission may be lowered and moved from under vehicle.



After transmission has been removed and put on bench, the top cover may be removed to allow gear access.

Shaft coupler must be removed after transmission output shaft is cleaned and lubed for seal protection and easy removal of the transmission adapter. Remove the shaft coupler and transmission adapter, being careful to capture bearing shims in the adapter. Check shim condition. The bearing race for each bearing is now free to come out of case housing.

Remove input shaft housing which also has a seal in it and the input shaft bearing race is now free for removal.





Remove plastic plug in front lower portion of case, then remove case snap ring retainer. The countershaft bearing race is now free to remove. With brass drift tool, tap the counter shaft(cluster gear) shaft toward front of case. Support the gear so as not to score shaft surfaces. The rear cluster bearing will drop free and the front cluster bearing will remain attached to shaft being driven out. The front cluster bearing may be tapped or pressed off after snap ring has been removed. Leave cluster gear in case.











To remove mainshaft gears, rotate input shaft until short syncronizer teeth are toward the cluster gear. Tilt input shaft forward and out of case as far as possible for clearance while lifting mainshaft gears up and out of case. Do not drop syncronizer parts which are loose at this point.

Bearings may be pulled from input shaft, and output shaft. A thin die grinder may be used to cut the cage and inner cone being careful to avoid cutting shaft surface or gears. The cone may then be cracked at the cut with a cold chisel, to allow removal. As output shaft inner cone is removed the gear and roller bearing halves are loose and must be captured.



Assembly:

Input bearing ,bearing race Koyo # JM205110

Output bearing Koyo #25572, (NSK #4725572), race #Koyo hicap #25528

Countershaft Koyo hicap #30305JR, race #Koyo hicap 30305J



Cool input shaft, output shaft, and cluster gear shaft overnight in freezer for them to contract as much as possible.

Heat cluster gear and all bearings in oven to 200 degrees F. for thermal expansion.



After oiling press fit surfaces, use bearing driver(suitable pipe) and tap bearing onto input shaft quickly and smartly before either has a change in temperature. Now, oil surfaces and install heated output shaft bearing onto output shaft. Set both aside for later assembly.



Repeat procedure for the correct end of cluster gear shaft (cold) front bearing. After bearing is installed on shaft, install small snap ring on end of shaft to retain bearing.



Insert (cold)cluster gear shaft through front bottom hole aligning it thru (hot)cluster gear, then tap it with brass drift pin to the end of the cluster gear--This should be easy fit. Raise rear of case to verticle position and position front of cluster shaft onto a suitable socket to support the shaft upward against cluster gear. Insert (hot)rear bearing downward onto shaft and continue to tap bearing onto shaft through rear of case. Set case back to horizontal position.



Install front cluster gear shaft race retaining snap ring in front bottom hole in case. Cluster gear assembly is now complete, and is to be left resting in the bottom of case till mainshaft is installed.



Reinsert input shaft forward in case; insert output assy into rear of case holding gears up at angle while realigning the short syncronizer teeth on the input shaft and simultaneously mating input to output gears--with the syncro ring in place.





Setting endplay preload



Install outer race in front input shaft opening, then install input shaft housing. (Option: Permatex #3H may be used on gasket surfaces of housing after new seal has # has been installed). Torque 13mm bolts.



Install new bearing race in mainshaft rear openings being careful to center bearings and seat races fully. Reinstall corresponding shim pack and check for end play. Only snug adapter to case with bolts. This may be done by rotating the shaft while tightening the bolts in the plate. If plate is extended when mainshaft binds shims must be removed and try again. End play should be zero, but there should be little or no preload (maybe . 001" shim should cause shaft to bind, if so remove more shims). When shims have been added/removed in . 001" increments to the point that the input shaft will not wiggle laterally with light force, and there is little perceptable drag--the main shaft preload is correctly set.

The countershaft shims must be added until there is less than . 001" endplay as measured on a dial indicater setup on the shaft. 2 screwdrivers inserted in the case and used to force the countershaft longitudinally in each direction will provide this movement measurement.

When preload adjustment is accomplished, rear extension adapter housing may be reinstalled with new seal pressed in. Lubricate output shaft splines to prevent seal damage, then put light sealant (read thin so as not to change preload) (Permatex #3H) on rear plate and put both shim packs in place, reinstall--using extreme care to keep both shim packs in place. Torque all studs.



Put grease on plastic plug and install in front bottom opening.



Remove input shaft housing, and reinstall with new seal pressed in and light sealant on mating surfaces. Lubricate input shaft splines so as not to damage seal.



Flush with clean kerosene 4-8 times or until no particles are found in the kerosene filter, during recycle and blow out gears to clear all dust particles.



Fill transmission with 4-1/2 qts of 5-30(Dodge) or 10-40(Harrys), or 5-50(Jeep transmission guy) or Castrol Syntorq(new 96 Dodge only) lubricant to fill hole in side of case. Using the side plate top hole, 6 quarts may be used to fill transmission.

Top cover may be reinstalled with sealant on mating surfaces.



Install transfer case shifter bracket on transmission after installation of transfer case so as to avoid interference with the transfer case mating nuts on that side of case. Adjust mounting plate full forward in the slots so boot won't be stressed in 4-low. Reconnect wires in 3 places.

 

[MMiller]

Thanks again EZGZ.



Hey Pastor, I think this needs to be a sticky!! Can this be looked into? What about the Dana 70 rebuild discussion too? With our trucks getting up there in age, most have or will need this info in the near future.



Michael

 

[1stgen4evr]

Michael

The snap ring pliers that I mentioned are KD # 2012. They are extremely helpful on the large snapring at the front of the countershaft. Another thing I would add from my experience is that you will want a sturdy table that is a good work height. I have several blocks that I can securely position the transmission in a vertical position when doing the shim work. I have considered cutting a hole in the table for the input shaft to set down in. In the event that anyone is making a transmission from the remains of two, be sure to use the shifter on the case that it came from.



I would second the idea of a sticky on the getrag rebuild. The write up that EZGZ has done is excellent.



I think Pastor may be waiting on me to write up the differential repair sticky. I will try to get off dead center on that soon.



1stgen4evr

James

 

[GMichaels]

getrag

When you lower the engine/trans just before transmission removal, would there be a problem with the exhuast? seems like there would be stress on part of the exhuast system

 

[f.boyle]

Thank you EZGZ that will help a bunch when I get to yanking out my getrag. not sure if it needs rebuild or just the clutch but either way I apreciat your help.

Frank

 

[RGuzzo]

Thanks EZ Im about to tackle this and all help will be appreciated. Between yourself and 1stgen4evr and the dodge man. I might just have the 90 on the road soon .

 

[EZGZ]

I had a good friend that had just done the rebuild help me with mine. He is a tinner. He drove 250 miles and brought some tools and the bearing kit. I have helped him build several VW sandrail transmission's and he was out of work and glad to help.

The first thing we did was take out the bench seat and then he looked at me and grinned as he reached for his power snippers. "You ain't gonna like this he said, but shut up and stay out of my way" He then commenced to hack out a giant whole in the floor of my truck so we could get my cherry picker in action and lower the transmission back and down with the transfer case attached. He patched the floor good as new.

 

[1stgen4evr]

On that hole in the floor. I have PMed with a couple of folks on that and here is what I said. The older fords chevys and dodges had a cover that you could remove on the three quarter and one ton models but not on the half tons. (If you go back far enough, they all had a pannel in the floor. ) In fact the floor was not the same on the two. So what you are about to do is not unheard of. I think Dodge has made the same floor on all their trucks and if you find one in the salvage yard that you can cut a panel out, that will insure that you can put it back snug and sound proof. Cut the replacment pannel about an inch and a quarter larger than what you will cut on your truck. Lay the cutout on your floor and mark around it so you can then install the larger pannel over the hole with screws and have a nice job. Smooth the edges on the hole and the cutout before you start to work on removing the transmission. An edge cover of duct tape on the hole will help also. (I hate the sight of blood, especially mine. ) Should your problem be only a situation with the shifter, you can do whatever is needed through the hole. There are some pictures of what the cutout should be that were posted a while back but as a guide, remember that you are accessing the bolts that hold the transmission to the bell housing and that you want to be able to remove the top of the transmission through the hole. Up near the heater ducting, remember that you have to put screws in that area when you are reassembling the new floor pannel. My 70 model ford was big enough that I could reach the bolts holding the bell housing to the motor as well as the ubolts on the joint.



On stressing the exhaust etc. , there is some flex that will allow the assembly to move down on the rear. I have not experienced a problem on my truck and the transmission has been out a total of four times in 400k miles. It doesn't take a lot of drop. And the rear of the engine should be supported while the back support is not holding. In fact, with the floor cutout, there may be no reason to drop down any at all if you are twd.



With the floor out, I changed the transmission on my ford with a come-along and a crude tripod over the transmission. The weight of the transfer case and transmission will make that a bit harder but with a cherry picker, you can complete the job one man. I hope that you have a friend that will help as it is nice to share the success and aggravation along the way.



1stgen4evr

James

 

[MMiller]

On my pulling truck I did the same. Cut the floor out of an extra cab I had, then cut the hole slightly smaller in the cab in my truck. It goes from the bottom of the firewall to just under the edge of the seat. I drilled holes and use 3/8" bolts and nuts to hold it down. A little overkill, I will probably do it a little differently if I did it again. I can remove the seat, remove the hump, and then like said above stick a cherry picker through the cab door. It will balance pretty well. I really don't like being under a truck with a heavy cast iron transmision, and tranfercase "sitting" on a transmission jack above me. I feel safer knowing that the assembly can fall off the cherry picker. I have not done this with my diesel as I am in hopes on not working on it too much. With my pulling truck it is inevitable that stuff will need to be fixed.



Michael

 

[GIT-R-DONE]

Question for you: what kind of oil (synthetic ?) would you use in this transmission? Is there an additive to also use ( like a friction modifier ) , and should this transmission be overfilled by a quart?





Some of you know that I was helping out a friend of mine with his transmission. We finally found one and will be installing within the next week or so. Just want to do this right the first time, and will be on the lookout for that service manual too. Any other helpful comments/suggestions on the install is always welcome. Thanks

 

[1stgen4evr]

oil and overfill

There has been considerable discussion on the type lube for the getrag. I think most will suggest a light weight synthetic and also to do the "overfill" thing. You can park the truck in a ditch with the driver side low and get most of an extra qt in the transmission. While you are under the truck, take a look at the way the transmission tilts toward the rear. The so called overfill isn't really overfilled but rather just compensating for the tail low mounting. The extra lube will insure that the front workings of the transmission are well lubed.



I have run 85aw in my transmission (getrag) for the last 325k miles and it is doing fine. It does not feel the same shifting as the light weight lube. It has never been rebuilt and presently has over 450k miles. So 'pays yo money and takes yo choice'. What the transmission won't tolerate at all is low lube.



James