C4 questions

[Whateverman]

as far as driveshafts : i had my existing driveshaft (front half) cut and got em to replace the steady bearing @ the same time,they gave me some grief about the centre slip joint being a little worn, but it balanced out all right and hasn't caused any trouble in the god-knows-how long its been in my truck

[tmcalavy]

Hey guys...checked out the C4 and brought it home. Some pix are attached. Fluid was due for a change...deep red but not black and no burnt smell. Has the dipstick and linkage rod for rod shifter...shifts through all positions. Came with a 156-tooth flexplate that has a couple of bad teeth so I'll replace that. No slipyoke though so I'll have to get a 28-spline yoke for it. Pulled the pan back at the house and pulled and cleaned the filter. There was a little crud in the pan and filter, but not bad. Next step is to haul it to a reputable tranny shop and have them check it out and service it. Can a good tranny shop actually run it to see if it pressurizes and shifts all right? The splined tail shaft has a little play side to side...is that normal?
Is there an online site that will tell/show me how an auto tranny bolts up to an engine that you guys recommend?

[fordman]

there is nothing special about how to bolt it up to any engine as far as i know. bolt the flywheel onto the engine and then botl the enigne to the transmission. make sure to line up the flywheel holes with the torque converter studs. while you bolt it all together. i think that shift arm should work fine with a stock rod from the column. but it does look to be missing the kick down lever from the nut on the nss on the side of the transmission. it should look something like this.

[tmcalavy]

Thanks fordman. So the flywheel/flexplate doesn't actually bolt to the torque converter, it bolts to the back of the engine and the TC studs fit into holes on the flexplate when they are mated/bolted together. I was really scratchin' my head yesterday looking at the TC studs...couldn't see how you could have the flexplate bolted to the TC and engine. Now I know. Hmm...maybe I can find a kickdown lever somewhere. Is the kickdown feature really necessary...could I drive the truck without it until I find the lever in your post? I do mostly in town, granny driving and only put the truck on the highway to haul the boat and dog to the lake occasionally. Anyone know the going price for a bench inspection/rebuild for a C4 nowadays? The guy I got it from said it was shifting good when he pulled it out, but you know how that goes. Will this 2000 stall TC work behind a 300 I-6 or should I get a stock one? Thanks for all the help. Can't wait to get the 300 I-6 and get started on the swap.

[fordman]

the torque converter studs are threaded. and once they go throught the flywheel you put nuts on the studs to hold the studs tight to the flywheel.

the kickdown is also known as passing gear. it is only used when you go to pass someone on the highway.

[tmcalavy]

thanks again fordman. got to get a list of parts ready, haul the tranny in for inspection and go run a compression test on the I-6 tomorrow...progress continues

[tmcalavy]

Well, I talked to the local cat-daddy of transmission building/rebuilding and he said nix to a C4 behind a 300 I-6...for my purposes at least...daily driving (town & hwy.) and light firewood and boat hauling. He recommended an AOD '88-'92. What say the forum...is he crackers or is he on to something? Any input welcome and appreciated.

[Whateverman]

I think the trans guy wants to sell a trans he has kicking around,but i'm cynical.
Having overdrive is nice,but unless your going to a fuel injected setup i'd avoid the AOD and go with a C6 if you're planning on working your truck on a near constant basis.
If you're just putting around most of the time a C4 will do ya fine,i've pulled 6000+lb travel trailers with a c4 in my truck (over a mountain) without any problems (except for smoking hot drum brakes- )- i wouldn''t do it daily and expect to have a trouble free tranny for ever ,but i wouldn't worry about it if that was a once in a while thing
what gearing does your truck have?

[Whateverman]

i should add: i never use the factory trans cooler,i use a towing one rated @ about 11000 lbs

[tmcalavy]

I have a Dana 60 rear end with 4.10 gears...not the best for road travel, but the most I will ever haul is my 2500-lb. boat or maybe a truck bed full of firewood. Right now I'm investigating an I-6 with a C6 behind it...for the right price that may be more do-able than rebuilding the C4, mating it to an I-6 and having to alter the driveshaft...only time will tell. I think I'll pass on an AOD though.

[fordman]

i wouldnt use aC4 or aod in a F250 with those tall gears.

[tmcalavy]

What's the downside to tall gears behind a C4 or AOD? Shifting too soon and lugging the engine?

[fordman]

the c4 isnt tough enough to pull the gears i would think.

[Whateverman]

having deep gears (like your 4.10's or some 3.73's ) would lessen the amount of strain on the trans itself (but you'd spin that poor ol' 6cyl up pretty high on the freeway),if you were running something crazy like 2.73's and trying to tow a big trailer with them then you'd be risking screwing up the trans.
I had a f250 parts truck that had a 240 with a c4 & 4.56 gears in the rear, according to the original owner the tranny outlived 3 engines (the crazy old bugger kept replacing them with 240's rather than stepping up to a 300),but died due to the trans cooler in the rad leaking antifreeze into the trans lines (the same thing has happened to me twice and resulted in the deaths of 1 c4 and 1 c6)