4spd to 5spd compatibility?

okay i know this has been a topic before but it was never really answered clear. i have a 4 speed tranny in my truck now, i recently picked up a 5 speed and tore it down. everything is fine with it and is ready to be installed into the truck. however, while i was at the dealer today looking for a bushing part for the shifter a few question arose that i didnt even think of as posing as a problem. im unsure as to what year the 5 speed came out of but it looks identical to my 4 speed only with a little extra hump on the end where the mount goes (im assuming because it has an extra gear...obviously). just so its clear for anyone else searching for this same topic here are my questions:

the transmission mount, are they the same for both 4 speeds and 5 speeds? looking at them at advanced autoparts on their computer they both show up as being the same, however i heard they are different. which is it? and whats different about the mount? are the holes in different locations on the trannys? visably they look to be in the same spot when comparing.

toyota shows there being a few different shifters. will my 4 speed shifter work in the 5 speed transmission? the reason i ask is because the 4 speed shifter in my truck is the only one i have. if it doesnt work, does anyone have an extra laying around for the 5 speed?

and lastly, is the 5 speed transmission longer than the 4 speed? in otherwords, will my driveline that is turned by my 4 speed work fine without binding anywhere with the 5 speed tranny?



thanks in advance guys, the help is greatly appreiciated.

bump....anyone?

Okay here is my understanding.

I have to transmission mounts in my garage. One is for a 5 speed and one for a 4 speed. The 4 speed has the same mount to the crossmember as the 5 speed does, but the cradle that attatches to the transmission is different. The 4 speed is wider.

Also, I do know that there are some different 4 speeds that where real oddball transmissions. I don't know what type of trucks they came in, but they are toploaders. We have a few in the transmission class, but mostly the 5 speeds like mine. But you said yours looks almost the same as your 5 speed, so I'm assuming you have a standard 4 speed, a center support.

I don't know if your shifter will work or not. I say stick it in and see if it shifts into all gears. If it doesnt work, I can get you a shifter assembly from my school. We've got an easy dozen Toyota 5 speeds.

As for length, I can measure them. But I would think you could measure the ones you have to make sure.

what year is your truck and what year did the 5 speed come out of? I believe all of the mounts are the same for all of the 2wd transmissions as long as your shifter comes out of the top. I think they all came out of the top even on the 4 speed (like 82 and newer or something). I would mostly worry about the rear end gear being different. in my experience the 3rd member from a 5 speed won't even fit in the housing of a 4 speed rear end. the 4 speed has a larger diameter on the ring gear than a 5 speed. I have a 90 pickup that had a 4 speed and i changed it to a 5 speed so i just swapped the rear end. I used the same drive shaft.

while i'm on my rant about toyota transmissions, i'll add a few more things. I work at a salvage yard and i've noticed that older celicas and non turbo supras have the same housing (at least on the outside) as a most pickups and even tacomas. (bell housings differ but interchange) I put a 87 non turbo supra 5spd in my hilux (i had one out of a 90 pickup but the supra rear end gear ratio is closer to that of my 75 hilux). The shifter was farther back but i just installed the pickup bell housing on the supra trans and moved the hole in my floor back. My 90 carbeurated pickup had a 4 speed and the transmission looked totally different than the trans out of my 75 (which was out of a 90 EFI truck. The speedo hookup is on the opposite side and the transmission mount (the one that bolts to the welded in part) is longer than the one on most trucks. I had a 5 speed out of an 89 pickup with a carb. 22r so i used it. the housing on it is the same as the 90 4spd. I have only seen 2 different styles of housings, but they will all fit in any truck i've run across as long as you have the correct trans mount (all the rubber ones seem to be the same) and speedo cable. The only other difference i've seen is shifter placement, but i think you can change all that out if you take the trans far enough apart. I hope all of this isn't too confusing, just some shit i've picked up from owning 30 toyota trucks.

Edited: 4/12/2007 10:42:36 AM by HOLCOMBE347

my 4 speed transmission is in my 88 pick up as of right now. it was the stock tranny for this truck when it was bought new in 87. i have a 22r in it btw. as for the 5 speed transmission i got, it came out of an 86 pickup with a 22r in it as well i believe. i had the chance to look at both transmission side by side on a work bench and they look very much alike. at first glance it would even be hard to tell them apart. the 5 speed has a little extra hump on the rear just before the holes that bolt to the tranny mount. i havent had a chance to get a tape measure out and measure everything yet, im going to get on that this weekend. as for the mounts, there is a difference. i was able to get advanced autoparts to order both the 4 speed mount and 5 speed mount. they look very similar but the piece that mounts to tranny itself is a little deeper on the 5 speed. also, its missing an adjustment screw. my 4 speed mount has that adjustment screw whereas the 5 speed doesnt. im not saying that both mounts arent compatible with each other, but from what i saw there was a difference. im going to try to reuse my 4 speed mount cause its almost new anyways but if not, no big deal. my main concern was with the drivelines. im almost certain they are the same length for 2wd std. cab trucks but just wanted to make sure, but like i said before i'll measure it this weekend before i pull it out. as far as the rear ends go, i have heard of there being a difference but the difference depends on what motor/ tranny type. while at the dealer the other day i noticed that there are 4 different 5 speeds i think so the rear ends were slightly different as needed. on that same note though, ive heard it isnt that big of a difference to make it hard to turn. in otherwords the motor shouldnt have any trouble turning over in 5th gear. either way, having the 5th gear in there it will bring down the rpm at higher speeds which is good because latley ive been having to do a lot of driving down straight flat roads it would be nice to sustain 75-80 without listening to my motor spin its ass off.

in your first post, are you referring to the tail shaft on the transmission being a different diameter? i know there are different tail shaft seals for the trannys that went in the diesel truck because those drive lines were slightly bigger. i konw this from experience...i got the wrong seal for my 4 speed put it in, and it leaked like no other. as far as the 5 speeds though, im unsure of that...i will be sure to look into it this weekend. thanks for all the help!

i just talked to my buddy tim who i forgot had done this swap before. he said there isnt any difference. only the mount...everything else bolts up and works like normal...even the drivelines.

I was talking about the ring gear in the rear end being bigger on the rear end that goes with the 4 speed. My current daily driver is the one that I did the 4 to 5 speed swap on. I drove it for a while before I swapped rear ends and it was kind of wierd because i hardly seemed to have to use 5th gear. If i got to 5th i was flying. I had the factory size tires. If you have a lower over all wheel/tire height it may work out better for you and even things out a bit. I used the same mount on mine but it is the other style trans that I was talking about above. You're probably right about the difference though, I think that every time I work on a toyota i find more subtle little differences.