I remember someone asking about the top-shift conversion (sometimes called the Jeep conversion) on a standard 60s/70s era Ford toploader four speed transmission not long ago. Couldn't find that specific thread, but a local shop handled these conversions years ago, and I had some info in an old notebook that I just dug up on this fairly simple modification. I say "fairly simple", because it DOES require transmission disassembly. To many, the inner workings of anything containing gears is hailed as some sort of Blark Art Voodoo, but they're really not all that difficult to work with. As Enjenjo stated once, "Rebuilding an engine is far more complicated than rebuilding a transmission, yet most people dive into engines without a second thought!". I agree, but most folks still fear the gears! When I worked at the AMC dealership back in the 80s, you could still buy the 70s era Jeep CJ5 top-shift assemblies over the counter. I doubt that your local Chrysler/Jeep dealer is still going to have such parts in stock, but ya never know! If the dealership has been there long enough to have been selling new CJ5s, it may be worth a phone call or visit! Never can tell what may be gathering dust on some shelf in the back of the warehouse. What you're looking for, is the complete top-shift assembly from CJ5 models throughout the mid-late 70s for sure...possibly some earlier. Jeep CJ guys and gals are worse than VW folk...they never send one to the junkyard unless it's been COMPLETELY gutted of ANYTHING usefull, so don't hold your breath waiting to stumble upon a stick shift Jeep in a wrecking yard with the top-shift assembly waiting for you! However...Jeep guys ARE car guys, and if you're in tight with the local 4x4 enthusiasts, you can often get deals on stuff like this that they may have stashed away in their garages. They won't bite...I did the 4x4 Thang myself for years and car guys are car guys. Getting the top-shift assembly off of a Jeep transmission is pretty easy stuff...remove the bolts holding the aluminum shift cover to the top of the transmission and carefully lift the shifter assembly up and out with the shift forks and all. Be sure to take the bolts and all related hardware, too. Now, once you've cleaned up the Jeep assembly and want to install it in your Ford Toploader four speed transmission, you're going to have to get a little dirty, and get inside the transmission. My best advice is to buy a service manual before attempting this, or have someone who knows transmissions help you out. They're not THAT complicated, but if you've never done it before, you can jumble up the parts and make things way too difficult on yourself later. Best to spring for a shop manual and perform the disassembly in the prescribed order. The basic operation involves removing the side-shift levers and internal shift forks from the Ford transmission, and installing the Jeep top-shift assembly where the sheetmetal cover is on the Ford unit. This gives you a rugged four speed manual transmission with the shifter right on top, which is perfect for hot rods from the 20s to the 50s. It puts the shifter centered in the transmission tunnel rather than offset to the driver's side, making gear changes and cabin space much more pleasant. It also looks more correct in an early rod. To do this job correctly, you will need to disassemble the transmission. There will be some grinding required to make the Jeep shift forks clear the opening in the top of the Ford case and work correctly, but it's not a big deal. Obviously, you don't want to be grinding on the case housing with all the internals in place! The area that will need the attention of your grinder is on the driver's side of the transmission near the back of the openiing on top where the new shifter assmbly will be going. I've done a crude diagram here to give you an IDEA of where you'll need to concentrate your efforts, but check it out for yourself, and take off a little at a time until you've got it right. The diagram isn't exactly to scale, and you may have to cut into an existing bolt hole in the case to gain the proper clearance, but use the Jeep assembly as your guide. Go slowly and check your work often. You can always take more metal away if need be, but it's pretty hard to put it BACK!!! Work carefully...this is the only part of the swap that isn't a "bolt on" affair, so take your time and do it RIGHT. Toploader transmissions and cases aren't getting any cheaper, so work carefully! (A side note here...there really IS a Ford toploader transmission that came in late 70s V8 Granadas that looked identical to the earlier cast iron toploaders, except that the cases were made of cast aluminum, and 'fourth gear' was an overdrive ratio. I've owned several Granadas with this transmission, and can verify that they are indeed FAR lighter than their cast iron cousins, and the overdrive fourth is a nice feature as well. The downside being that these trannys are harder to find, and they won't handle as much power as the earlier units...but behind a flathead or mild small block in a light car, you'll be fine. If you go this route, the aluminum case is much easier to grind, so be cautious as you go...don't over-do it!!) With the proper clearancing done, you can now give the empty case a complete cleaning to remove all the filings and metal particles you created while grinding. You can't make it TOO clean, so go at it with gusto! Next, you'll want to fit press-in plugs to the holes where the rods for the stock side-shift levers went into the case. A good auto parts place will have a selection of these "little freeze plugs" in their Dorman line, or other brand of plugs and hardware. Find the correct diameter plugs, give them a LIGHT film of RTV sealer, then tap them squarely into place. This will keep dirt out and the gear lube in! At this point, the transmission can be cleaned and reassembled as per the reapair manual. I like to clean my hands often and apply clean, fresh gear lube to all internal parts as I go, making sure that nothing goes together 'dry'. Naturally, this is an excellent time to inspect wear items such as synchros and replace as needed. Also check all gears closely to look for evidence of chipped teeth or improper wear patterns. Although tranny rebuilds aren't inherently difficult, you don't neccessarily want to make a new hobby out of tearing down the same transmission every weekend. It's worth doing once, and doing RIGHT. With the trans assembled, carefully install the Jeep top-shift cver assembly making absolutely sure that the shift forks go into the correct position and fit properly. This can be a little tricky, and is best done with two people...an extra set of eyes and hands is a big help in this stage, but one guy can do it with patience and care. Intall four bolts into the cover, two per side and snug them down. Then, check shifter operation. It should be smooth and precise with no gritty action or binding. If a problem exists, fix it now before proceeding. If the shifter operation feels right, install the rest of the top cover bolts from the Jeep transmission and install the tranny in your hot rod. DO NOT FORGET TO FILL IT TO THE PROPER LEVEL WITH A QUALITY GEAR LUBE!! New seals are a no-brainer...and they're available at nearly any decent auto parts store. That's really all there is to this slick modification...you can do it in one weekend if you're taking your time...a pro can do it in a few hours! There's no rush, though. Work carefully and ask for help if you need it. In the end, you will have a tough four speed transmission all freshened up and custom fitted to your hot rod project!
Would this apply to a Muncie 465 4-speed top loader ? I guess my question is, would the Jeep shift assembly work with that transmission ? Or should one go elsewhere.
So this modification must use a shifter unit from a 4 spd Jeep trans, right? Most of the stick Jeep trannys I've seen are 3 spd. How hard is the 4 spd to fine? Frank
It was also detailed in the Dec 1990 issue of Street Rodder. Have a PDF of that, a little to large to attach. Also have PDF of parts required and a blow up of shift tower. If anyone wants this let me know.
Early to mid '80s F150 2WD pickups used the top shift 4 speed O/D as well, and I see them occasionally at the swap meets around the Northeast.
Good stuff as usual, Hack. Minor non-essential detail additions: Jeep original tranny designation is the T-176 available in CJ-5 & early CJ-7 (have heard, but can't confirm, T-177 is same tranny w/different ratios, so top cover would fit) David Kee Transmissions (look 'em up online - I'm on painfully slow dial-up or I'd do it for ya!) is building brand new Jeep top cover/shifter assemblies. They also build all new toploaders as well. His new cases can be ordered with notch already machined in.
I'm 4x4 AND a car guy. Thanks Fat Hack for letting people know not to be afraid of us. And thanks for this great tech article. I'll try to add a little info. myself. T-176 trannies are not that hard to come by and although it is a fairly durable unit, many people building Jeeps these days are seeking deeper gears and stronger 3/4-1ton truck trannies. I see these for less than $50 on some of the Jeep sites and many times free. They are also sold for more, but if you're patient, they show up cheap. Also, the T-176 replaced the T-150 3 spd in CJs and ran during the end of the CJ production run (not the early CJ7s as suggested above). They can be found in '80-'86 model years. Typical casting numbers found on the T176 are C-2604203. Here's an excellent resource for info. on the T-176 and many other truck trannies http://www.novak-adapt.com/knowledge/t176.htm Must be a swap out of a T-150 3spd. As I stated above, these came in 80-86 CJs. It's a direct bolt on swap. I used to have the T-150 in my '78. Running a NP435 I built from a F250 2WD now.
I am sporting one of these little 3 speed beauty's in my 34 Coupe project. They are a great way to get that old time topshift id a fully syncronized tranny!
Levis,....I'm running a RUG 3 speed with the Jeep shifter behind the 8BA in my 40 pickup,... Love it !!!!!! 4TTRUK
just FYI....Ford made a TOD - 3speed with 4th overdrive in their late 70's and up to about 1981 as a mileage thing...mostly found in pickups....
The T150 top cover works on the RUG, and RAT three speeds. If you are looking for a TOD out of a Ford truck, make sure they don't sell you a SROD 4 speed that was used in the same era.
will these work on the RUG overdrive thats was offered in the ford pickups of the time? they look just like a toploader but 4th gear is OD?
Seems like Frank Otto did a in depth article about the T-10 jeep conversion in one of the Rod & Custom annuals back in the 70's. HRP
The shift pattern is different. The old third gear ratio was changed to became an overdrive. The shift lever was flipped over to swap 3-4 sequence with the external shifter. With a top cover shifter you would shift in a W pattern. Third in bottom right, OD in upper right.
The Jalopy Journal
