Engine/Transmission (1994 - 1998) Why!!!!!!!!!!!!

[CumminsPower98]

This is an old thread with an update at the end for those who remember it, thanks. Things are just not going right for me now days. I find three "good" used 6-speeds on here, one for me and the other two for others. The other two went fine but I end up getting shafted on my whole upgrade. First I found a front drive shaft for a 6-speed in the classifieds with low miles for a good price. Well I get it and it's bent and can't be fixed. My shaft was loose in the slip yoke so I figured it would be cheaper to buy this other shaft rather then rebuild mine. So my front shaft ends up costing me $310!



The 6-speed I decided to use seemed to have excessive mainshaft end play so I adjusted it. I wonder if this trany had problems before I touched it because it looked like it had hardly run at all compared to the other two and the thing was also harder to turn. Anyway so I install that trany and it has a shudder under load like something is binding. :{ I also had pilot bushing trouble. I had my flywheel bored out for the Kevlar bushing,which I got from South Bend Clutch along with the 0090 Con OFE 6-speed conversion clutch. Well the guy got the bore . 002 too small and was afraid to run through it again for fear of going too big. So he honed the bushing out . 002. Well I installed it and it was snug on the input shaft so I did some emery cloth work on it to help it fit. I got what I thought was a good free fit and put the truck together( trany install went very slick and easy). Now yesterday when I pulled the thing apart because of the trany problems I find the bushing has galded and there is . 006 worth of bushing melted to the input nose from the front half of the bushing (toward front of engine). Now I have to try to figure out what to do with the flywheel and try to find a trany shop. My truck is filling my work bay and I'm going into debt for all this. Sorry guys, I just had to vent my frustrations. I'm not asking for help.

 

[Boomer II]

Story of my life. I'll be in Moab Easter for the Safari and know a few people there, one is a Cummins owner.

 

[CumminsPower98]

I really enjoy the Jeep Safari. I don't have a Jeep but I can at least go out and watch. I really love all the carnage on Potato Salad Hill. I bet a number of TDR members come here for Safari and I think it would be cool to get together one evening or something. I have not met any other members besides my one friend here in Moab, Jim S.

 

[mschoenheider]

Easter in Moab is sweet, where else can you see TJs running around on 33s and think to your self "Why does he have such small tires?"

Always a good party at Potato salad hill and the dump bump.

 

[JTMcCracken]

Boy have I been down that road a few times! It's no fun but keep in mind it WILL all come to and end, and then when your friends start telling their horror stories you can participate! JTMcC.

 

[Boomer II]

I'm a member of the Red Rock 4WD club and lead trails out there that week. The group I run with all have Dodge trucks, we usually stay at Spanish Trail RV park, this year I'm at the Red Stone. A get together would be fun, post something and we'll see what we can throw together. Oo.

 

[CumminsPower98]

update

I have been thinking about my transmission problem all week and have decided to remove . 003 worth of shim from the main shaft. I hope this along with another flywheel that has not been bored out will solve my problems. I will install it Sunday morning and let you all know what happens. I figure that if the pilot bushing was out of center a few thousandths combined with the mainshaft maybe being too tight might have messed me up. It didn't really seem too tight to me but what do I know. Sure hope this works as I really need my ride back and I'm starting to have withdrawals.

 

[Dan_69GTX]

Please let us know what happens!



Who bored out your flywheel? What was the cost?



If it is out of center - any way to get them to fess up?

Or are the centers never perfectly centered in the first place and there just wasn't enough free play?



Thanks!

Dan

 

[CumminsPower98]

A little shop in a nearby town, Grand Junction, CO, did the work, it cost me $75 for the bore and a resurface. They told me up front that it would be hard to get true center without having it mounted on the crank. I don't know much about machine work so... They bored it straight down with the flywheel laying flat on some sort of milling machine? It was bored too . 002 too small, which they knew and were afraid to go through it again for fear of making it too big. So the bushing was honed out . 002. When I installed the bushing, which by the way was . 002 larger then spec. , it compressed down to a snug fit on the input shaft so I had to dress it a bit with fine emery cloth. I got it to what I thought was a good fit and everything went right together. First startup everything worked fine with no binding in the bushing but in a very short time it started binding up so I was not able to shift into gear. Then it started working again later. When I took it to the shop last Sunday to pull the trany I was moving it around to get in place and it bound up again. This time I could not get it in gear so I turned it off and put in gear and started it again. It must have been stuck pretty hard because the truck tried to move ahead as I started it. Anyway once I got the thing out the input shaft had '006 worth of bushing melted to the nose. Anyway sorry so long. Can't wait to get this all figured out and back on the road again.

 

[Joseph Donnelly]

At this point, if you don't have another flywheel, I think I'd make up a plug that is a moderate press fit in the hole, press in with green loctite. Then rebore for a regular oilite bronze bushing that fits the stock wheel--1" OD, . 75" ID. If the shop is any good, they can center it using the rim of the recessed area where the bolts and bushing are.

 

[CumminsPower98]

Joseph, I already traded South Bend Clutch and got one with the original needle bearing in it. They will then fix mine and charge me whatever that costs I guess so I'm good to go there. I wish I would have just gone with the needle bearing in the first place as it's costing me but I just have to live and learn. I installed two other clutches from SBC using the Kevlar bushing not long before mine. They both hung up a little to begin with also but not so bad and they cleared up soon. All I can say to anyone reading this and wanting to run a Kevlar bushing, make sure you are using a really good machine shop or better yet just trade flywheels with SBC. Like everyone has said, Peter is great to work with.

 

[CumminsPower98]

Update

Well I tried the 6-speed again this morning and now I get the worst shudder in 2nd gear and can hardly tell it in 3rd. I can't really feel anything in the other gears either so now it's mostly 2nd with the problem. It shudders on acceleration or deceleration at about the same rate. So I am pretty sure now that I indeed need to find an expert to get this thing sorted out. At least my pilot bearing is for sure correct this time around so I made a small step in the right direction.



P. S. 1st gear shudders also, it's just harder to tell because I can't load it much.

 

[CumminsPower98]

Update

I sent my 6-speed to Standard Transmission in Texas and they couldn't find anything wrong!! They said everything in there look like new. I gave them my symptoms again and they kept checking it over. Finally they ended up replacing the 1st and 2nd gear brass parts of those syncrose because they had a little wear I guess. They put it all back together with the correct setup and shipped it back to me. I installed it this evening and guess what, I still have the same problem. I spent $385 for their work and about $398 on shipping. Now I guess I need to call them and see what they say. I am getting really tired of taking this thing in and out and being without my truck for sooooo long. I can hardly get it into 1st now also, I'm hoping this will break in. I might just drive it and see if the problems clear up.



Mark

 

[Dan_69GTX]

Hi again,



I know you have probably checked everything several times, but what the heck - I'll throw in my 2cents here again.



Could it be the drive shaft/carrier bearing? Everything look fine there?



Have any good friends with a similar setup? See if you can persuade them to use their parts. It would be a lot of work, but hey - sometimes it has to be done.



See about using their driveshaft - maybe even transmission - or use yours in their truck. Yes it is a lot of work, but it is a place to go from here.



Does it shudder in 4X4? What about removing the rear shaft, plugging the transfer case and driving it in 4x4 (make it just use the front shaft for moving) - does it still shudder? If so, it isn't the rear shaft/or driveshaft angle.



If I think of anything else, I'll post it. Thanks for keeping us updated.



Dan

 

[scramblin]

Originally posted by Dan_69GTX

Hi again,





Does it shudder in 4X4? What about removing the rear shaft, plugging the transfer case and driving it in 4x4 (make it just use the front shaft for moving) - does it still shudder? If so, it isn't the rear shaft/or driveshaft angle.



If I think of anything else, I'll post it. Thanks for keeping us updated.



Dan

Usually by putting it in 4x4 you can determine if its a rear driveline problem.



BTW. We will be at the Moab EJS. Oo.

 

[CumminsPower98]

I have not even put the front driveline on yet. The last two times now I have installed the trans with the minimum stuff required to drive it although I did put the floor together cause it was so noisy. I will install the front shaft and see what happens. I really don't think the rear shaft is a problem though because it is all fully rebuilt and the trans only acts up in a few gears or at least that's all I can feel.

 

[DuallyDean]

CumminsPower--



Rebuilding a driveshaft won't fix a bad carrier bearing, and that type of shudder would be worse in the lower gears than in the higher gears. I have a standard cab, so I don't have this item to worry about, but a friend has a Quad Cab, and replacing his carrier bearing solved his shuddering problem. (it's also a lot easier to replace and rule out as a problem than pulling that transmission again!)

 

[CumminsPower98]

The carrier bearing was replaced when the driveline was worked on but I wanted to go ahead and rule it out some more so I replaced it again and no help at all.

 

[DuallyDean]

C P '98--

I don't envy you. I hate to say it but I think swapping in your buddy's transmission may be the next step to isolate what is causing the vibe. Best of luck.



Dean

 

[scramblin]

What about the transmission mount? In one of my jeeps I couldn't get rid of the shudder untill I changed the rubber transmission mount to polyurethane. Also have you checked the pinion angle?