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I hope someone out there can help me with my problem. I have completed a 4BTAA conversion on my old truck, and I elected to go with the getrag 360 as it was available from a totaled 93 Ram 250 (231K) I purchased from the original owner. My truck (a 1/2 ton 1971 DODGE D-100) was originally a v8 automatic. Everything is working great, and having had it on the road just since 9/6/08 everything is not yet considered "proven", however it has not received a "days rest" since start up. My problem is just this: I see no provisions for setting free travel in my clutch, there is nothing there to keep the throw out bearing from riding against the pressure plate, and that concerns me for the life of the bearing. I do not see any provisions for a return spring, or what ever they may have had, and the books I have do not show, or reference such a part, somebody please advise, this is my first encounter with this particular transmission.

The Truck:
1971 Dodge D100 1/2 ton 2wd long bed pick up, was originally a 5.2 318 v8, A727 Automatic 3.23 geared rear end, PS, PB, and Factory A/C
The conversion:
4BTAA Cummins (P7100) running all stock, 3" straight pipe exaust all the way back, adapter plate, flywheel, starter, and Getrag 360 from a totaled 93 Ram 250 (had the 5.9, that I happen to still have, and don't need), I used the motor accessories from the 5.9 A/C, Alternator, water inlets, outlets, and mount stand from the right side, built my own for the left, vacuum pump w/power steering pump removed. Plans are to incorporate the A/C back into the original design's of the truck. The power steering has been removed in leu of manual steering. First fuel mpg logging revealed 27.778 MPG, and none of this was highway, my intentions are to increase the rear end gear ratio to 2.94, as with my current set up you just take off in second, and I can use the OD gear a little sooner than I would like too, so I believe even better milage is there to be had.
Built/building for a daily driver, occasionally will haul a load, boat, car trailer, firewood, etc. :beer:
 

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There was no provision for setting "free travel clearance" in your set up. You could drill the bearing fork arm at the slave cylinder area and make a mounting tab on the engine adapter for a spring. I looked at doing that but got impatient and put it together the way it came from the factory. Overall it is a poor design because it runs the release bearing and it is another reason why to replace the bearing everytime the transmission is removed.
 

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I have yet to see a hydraulic activated clutch assembly that was built with any an adjustment for "free travel clearence", shows you how well they build throw out bearings! My 92 Dodge only has 173K miles and I'm still on the original clutch and throw out bearing, but on the second pilot bearing, ready for the third.
Do you self a favor and fit your flywheel with a sealed pilot bearing.
 

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Discussion Starter #4
Thank you BobS, and to you scout4bta for your replies, and starting with you Bob, I kinda figured as much, but I wasn't sure, and I had no way to prove it either way, I am used to old school clutches that are strictly mechanical, so I expected I needed a way to obtain free travel, well that eases my mind a bit, I guess we will see how long this bearing holds up, and then again, I may try to fabricate something to make for some free travel, some how I feel old school knew best, why would you run a bearing without reason, thanks again for your reply!!!!

Scout4ba, I have not had much dealings with hydraulic clutches, and I can barely remember the last one I worked on, I guess as you said the designers knew what they were doing, and I am sure it must have worked, but I still don't like the idea, and I may fabricate provisions for a free travel adjustment, or may just run it and see what happens. I packed my pilot bearing (bushing) with a super slick high quality grease, I hope this prevents me from having problems with it, the pilot bushing in my 69 D-100 has given me very good service for many years now, unfortunately I cant say the same about the throw out bearing, I had to remove it and repack it after about 2 years it became noisy, and I know it had adequate free travel. That Truck: A stock 69 D-100 w/ 3.7 ltr. 225cid. slant 6 w/ HD 11" clutch and 3 spd manual transmission column shifted, I have been driving this one well over 10 years, it has logged well over 400K miles, and so far knock on wood, still running, however the engine is very, very tired!!!
 
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