rowdy235

Hi all,

For those who have not been following I've been working on my 78 pickup. I've finally got it running good, but will need a clutch soon from the feel of things. I was looking online at rock auto and noticed some clutches are marked "To 7/78" and some "From 8/78". Per my door panel mine was manufactured in 04/78. I really think they are advising after 8/78 may actually be a 79, but maybe not.

Now, most of the clutches for the "from 8/78" are 8-7/8" X 1-1/8" X 21T. The "to 7/78" options list one with the same specs and one that is the same except the spline is 1 3/16". I have a friend that works at a certain auto part store and he looked up and they show one clutch; no indication of manufacture date, with the 1 1/8" spline.

Now, my question, I would really like to upgrade to a heavy duty clutch (being as its a relatively heavy duty truck), trouble is the only two Rock Auto show are listed as "From 8/78" manufacture, but they list the 8-7/8" X 1-1/8" X 21T. Does anybody know if this will work? Are the splines on a 78 1 1/8" or 1 3/16"? The two HD varieties Rock Auto shows are with a steelback or 6-puck ceramic disc. Any opinions on this or any other clutches that may be good?

Now, my next question. Someday I would like to convert the truck to 4wd. I thought while I had the trans out to do the clutch would be a good time to get a head start. My truck has the L-43 trans. Is it possible to convert the 2wd to 4wd? Or would it be easier just to look for a 4wd trans? If so which is the easiest/best to put in?

rowdy235

So I've been doing a little more reading today. There is one particular clutch manufacturer that sells the 1 3/16" pilot diameter and list it for both pre and post july 78s. Not sure why. Anyway, figured out I do not want a 6-puck as they are more of an off/on switch than a clutch. Does anybody have any experience with ceramic vs a regular clutch?

83

My only experience with a "heavy duty" clutch was a Centerforce clutch, years back. It could have been an install problem on my part, but it started slipping a year later. I've heard they tear up flywheels.

In my experience, Toyota is best. They are already heavy duty. The clutch in my 98 is still the original clutch, with 200,000 miles on it. I've been pretty regularly towing a 3,000lb trailer lately, back & forth from Montana to southern Utah a couple times this year, and around the mountains. No problems so far.

I guess you could check out Marlin Crawler for advice on their heavy duty clutches and for a larger group of people experienced with them.

Not sure on all the manufacturing dates. I do remember from my 83, but especially from my 78, that part searches get a lot more complicated...they're out there still, but there's a lot more trail and error trying to find the right ones.

I know you've been around a while so you probably are familiar with the differences between the 2wd and 4wd trannies? You can convert, but because there'll be a transfer case attached to it, the 4wd tranny will be much longer, which means driveshaft mods and possibly crossmember and floorboard/shifter hole mods depending on what tranny you get. But yeah, you can do it. Any tranny bolted to an R series motor will both right up to any other R series motor. It's the other end that'll take some work.

83

Sorry read your post a little closer. The 2wd tranny can't convert to 4wd. Well...I mean anything is possible, but that's not the way you want to do it. The output part of the housing tapers down and you can't bolt a transfer case on there. Completely different housing than a 4wd tranny.

Even though all of us around here dole out the same advice on what trannies will swap in to first gen trucks and what modifications are needed, there seem to be very very few who have actually done it and can give you first hand advice. And your truck isn't even a first gen...so even less experience.

But it has been done and the advice we give seems to be correct. There were kits for Wolverines back in the 70s and 80s with maybe Dana axles to convert these trucks to 4wd. Not sure what tranny was used but someone will know...

Anyways, with some courage and fabrication/welding skills, you can put any tranny you want in there. But probably something from the early 80s will be the easiest fit. But honestly I don't really know...

rowdy235

Thanks for the response 83. I ended up just deciding on a factory clutch. Had a centerforce in my 98, didn't really do anything other than give my left leg a workout

As it stands- my buddy has an 81 4x4 and just bought an L52 to swap in for the L43, he is just going to give me the L-43. I think the best way to figure it out will be to bolt it up and go from there

83

Nice! That's a good start. So much of this depends on how much money you can throw at your truck...Ideally, the advice would be to pick a stronger tranny with 5th gear, since you don't want to do all these modifications for an old 4-speed transmission that you'll end up wanting to replace down the road with something better. Just start with what you want and do the modifications based on it.

But since money does matter...yeah, just do what you can. As far as I remember the L43 is good tranny, people just like to swap them out for a 5-speed. And it's actually the L52 that had some weaknesses.

Good luck! I think it's going to be crossmember and driveshaft mods that are the biggest issue. Well...until you get to the front axle stuff But for now you can just leave off the front driveshaft.

Bingle

2x on what 83 said except it was the L50 that was problematic, the L52 had the bigger input bearing.
Also, all L series trans were the same length so you could fab up for the 43 and swap for a 50 or 52 (5 speed) later.
Marlin Crawler has great tranny info on their website, FYI.

rowdy235

Yeah, I'll keep an eye out for a 5-speed, but people seem to be pretty proud of them I've noticed.

I think my buddy has a crossmember for that L-43 out of the 81; I wonder if that could me made to work with the frame on the 78?

83

Probably.

It's all a matter of measuring or test fitting. Most of this stuff won't bolt right up, but with welding or drilling, it'll fit!