4 Speed Swap (1 Viewer)
- Thread starter rsalber
- Start date
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Can't point you to a thread. You can use the same clutch and flywheel, swap in a four-speed bel housing, and the Trans & T-case will bolt in. You'll need four speed driveshafts, and the E-Brake will be tight to the frame cross member. My 74 came with a 4-speed with a "three speed" clutch and T-case.
Skreddy
SILVER Star
To keep the 3 speed t-case, you don’t need the 4 speed drivelines but you will need to have 1 shortened and 1 lengthened (no, they won’t swap).
You need the 4 speed bellhousing and get it with the fork and pivot ball. As said, the 3 finger clutch will work with the 4 speed.
For the 4speed with 3 speed t-case, you need a few of the longer bolts that bolt the two together: need to either buy them from somewhere or try to get them/keep them from the 4 speed t-case (if you got the whole assembly). Then you need a different input gear and a pto gear or spacer and a spacer for the rear of the input shaft.
Will also need to cut a shifter hole in the tunnel (unless going with a @Cruiser Cult 4 on the tree adapter….). Then also need to lengthen the shift linkage for the t-case, unless it’s floor shift or converting it to floor shift. The parking brake drum is super tight (mines 1970). I put 2 large fender washers under each side of the front engine mounts to lower the tail for better clearance (don’t forget to shim up the radiator so your fan doesn’t hit the shroud).
I probably missed some, there’s lots of threads. Cruiser Outfitters has a write up that details most of it on their website. I think I did a quick overview on the 403 4 on the tree thread that I can find if you like. Multiple vendors sell the parts needed. I got my parts from @65swb when I did mine Mark’s Offroad).
You need the 4 speed bellhousing and get it with the fork and pivot ball. As said, the 3 finger clutch will work with the 4 speed.
For the 4speed with 3 speed t-case, you need a few of the longer bolts that bolt the two together: need to either buy them from somewhere or try to get them/keep them from the 4 speed t-case (if you got the whole assembly). Then you need a different input gear and a pto gear or spacer and a spacer for the rear of the input shaft.
Will also need to cut a shifter hole in the tunnel (unless going with a @Cruiser Cult 4 on the tree adapter….). Then also need to lengthen the shift linkage for the t-case, unless it’s floor shift or converting it to floor shift. The parking brake drum is super tight (mines 1970). I put 2 large fender washers under each side of the front engine mounts to lower the tail for better clearance (don’t forget to shim up the radiator so your fan doesn’t hit the shroud).
I probably missed some, there’s lots of threads. Cruiser Outfitters has a write up that details most of it on their website. I think I did a quick overview on the 403 4 on the tree thread that I can find if you like. Multiple vendors sell the parts needed. I got my parts from @65swb when I did mine Mark’s Offroad).
- Thread starter
- #4
Thanks, I had a set of custom shafts made with long travel splines, so they may work...will have to find out. Mine is a 1971, do you know if I would need the H41 or the H42 transmission and bell housing? I appreciate the insight and information. I put an electric cooling fan up front, so that shouldn't be an issue with the fan and shroud.
Living in the Past
SILVER Star
H41, H42 and H55F all use the same bellhousing. Just need the bellhousing to match the engine. BF and H engines use different bellhousings. Also later transmissions (4/86+?) need some clearance ground for oil channels. F anH engines share the same import spline. B engines are different. Believe the later HZ engines were different as well.
