uh oh....

dont know for sure, i'll get under it tomorrow, but it dont sound good...

question is what tranny/tcase combo is "plug and play" for my '74 w/ .258

i have the T18A tranny and D20 tcase... i'd like to know my options if i have to replace/rebuild a tranny. if i do, i may be interested in a different combo to get a better crawl ratio. i love the T18A but dont like the D20 and the fact that only 3.15:1 is as good as it gets as far as after market parts.

i am running 4:88's in the diffs and its not a DD.

first thought after reading is NP435 and D300

thanks in advance.... and yes i am using the search feature, read about 20 pages here and 20 on PBB R)

 

the setup you have now seems decent. at worst, you're looking at ~62:1 crawl ratio if you only changed the x-fer case innards (and if the t-18 is close ratio). if wide ratio, you'd have ~62:1 as is. with the 3.15 innards, you'd be 97:1. all of those look pretty good to me.

i'm at 51:1

 

The only plug-and-play combo is what came stock: either the T-14 and Dana 20, or the close-ratio T-18 and Dana 20. Are you referring to the close ratio T-18? That's a T-18, not a T-18A. A T-18A is wide ratio, but a T-18 can be either wide ratio or close ratio, depending on the year/model.

Can't change the trans innards - there's no wide ratio input gear that's the right length for that app. You could go to a wide-ratio, but it would require, say, a Ford T-18 and a bell from a T-150/T-176 Jeep. That will be a different length from what you've got (ca 2" shorter) so you'll need to change the driveshafts and move the crossmember, minimum.

JMO - keep the CR T-18 if you have it. It's very strong and gives you a wide choice of final drive ratios. A possible change might be going to a D300 and Tera gears, which whould not be a low-bucks solution but would give you a 78:1 crawl, pretty decent for a streetable short-wheelbase vehicle.

 

Right, that '74 is a probably a 4:1 first. You could just change the guts over to a 6.32:1 first. The input shaft is the only issue. I guess some people get them shortened.

 

The 4.02:1 shaft is longer than the available 6.32:1 Ford shaft. You could maybe find a Jeep V8 FSJ shaft and have it shortened, but it seems like a lot of work when you could instead buy a Ford T-18, T-150 bell, and convert the Ford transmission. Then you'd (neccessarily) also have the advantage of a longer rear driveshaft.

Lots of options, but no real 'plug-and-play' solutions other than the original drivetrain.

T-18s are very durable, and if it's the source of the noise you can probably put new bearings, blocking rings and a small parts kit into it and it'll run for another 30 years. I think it's most likely something else though...

 

its not the 4:1, its the T18A.... i'd like the 97:1 if i keep the D20 and regear the tcase w/the 3.15:1 kit but want 100:1 or better... i've had my eyes peeled for a D300 but we all know how rare those are.... i was thinking aloud while at work the past 24hrs... reading all my options if i had the chance to start from scratch as far as tranny/tcase. new drivelines are not an issue... i'll suck it up and have new ones made.

i am about to put the CJ on jack stands now.... my first impression is that its in the rear end

i can feel it "popping" when i roll it on flat ground.... i hope and pray its shafts... next R&P..... last, please, please dont be the locker :?

 

at least you've got the desireable transmission gearing. fwiw, if you're willing to spend the money, i'd go with the tera-low in the t-case. that way, you'd make no other alterations. also, there's no way you'd be able to discern the difference between 97:1, which you'd have, and 100:1, which you desire.

 

looks like i'll have some time to think it over..... tranny/tcase is A 'OK. here's the 4:88's though

 

ouch

 

Carnage.

 

i'd love to have 5:1.... but that whole new rear axle w/new gears/locker would break the bank.... then i'm still not 6 lug in the rear.

thinking i will do the rear disc conversion, just get new R&P, maybe get the 3.15:1's for the D20.... unless i find a D300 before i put it all back together. it'll be on the stands for a while.... gonna use this time to get some thigs done right. still gotta mount my winch too.

 

Looks like a Toyota Carrier assembly. If so, when you put it back together get rid of the collapsible spacer (crush sleeve) and go with a solid spacer with shims. These are available from Randy's Ring and Pinion for about $23 or so dollars. The collapsible spacer has a tendency to collapse over time throwing pinion bearing pre-load out the window. This mod makes for a much more dependable diff. I do the same mod with Ford 9" and some GM's also. Nickmil

 

you're in my head.... even though the crush sleeve was fine, didnt seem to be the casue of the problem.... its gone. i'm going to randy's to get the spacer/shims :twisted: