Trouble Shoot My TH400

[Crazy_Jeepman]

I got my rebuilt 360 into my 79 Golden Eagle Cherokee. I have developed a problem. My trans seems to shift ok, however when I select 2nd it seems to drag bad, like I have a brake hung up. shift into Low it actualy frees up and runs out fine, shift it to second and it will power down and seems to take a lot of power to move it. Drive does fine. Any ideas. Thanks!!

[Rande]

I'm certainly no tranny guru but it seems to me it might be going into two gears at once. That possible?

[Crazy_Jeepman]

I have very little knowledge of Automatics as well. I am not sure if it is possible to be in two gears at once. I am leaning towards the valve body, possibly doing just that. I can't understand why it would work fine in Drive, only causes problems when I actualy select 2nd. :confused:

[Crazy_Jeepman]

Well, I see there is no advice on this situation. I would like to add now reverse is acting up. Again acts like a brake is on. Place in reverse or second, on level ground at an idle the Cherokee will NOT move at all, unless I give it throttle, more than usual. Anyone have any ideas throw em my way. I do not feel like swapping out a trany. I am not knowledgeable of how an Automatic works, so if anyone has any ideas let me know. :D

[64Trvlr]

Pete
Is it full of transmission fluid? Is the fluid clean and does it smell ok? Is the shifter moving through the detents ok?
:cool:

[Don S]

Hi Crazy Jeepman....How long since the filter was changed? The intake is on top and catches the crud as it drips down.. :mad: ..thus starving the whole sys. TEMP solve...over filling by 2 qts got me Home one time...450 miles. They say it's bad for the tranny......I've never been in one other than oil & filter.........sorry........ :( ...ds

[JB]

Well I wasnt going to say anything until I read your post about "reverse now acting up" .. I recently got my 727 serviced from a reputable Tranny mechanic, I was asking him if he thought it was shot because it would not engage in 1st until it warmed up..and the fluid was fine, He said, "usually before it needs a complete rebuild you will notice it acting up in 2nd and reverse" ..

[Banks]

CJ,I'm not a trans. "expert",but I just wanted to pass on my experiences.I've had many vehichles with the TH400,and in my opinion,its the best auto ever produced.I have run them out of fluid,pulled impossible loads and even threw one into reverse at 70 mph!I have never "broken" one.They operate on hydraulic pressure switching valves.The last 2 I carried in for rebuild[one had no 2nd or reverse]I was told there was nothing wrong except that there was dirt in the valve body that was not allowing shifting.{rebuilt anyway]My first 400 was in a 68 Chevy and it was slow to shift,so I installed a B&M shift kit[stronger valve springs]and it would snap your neck going to 2nd.I'm not crazy about"speed shifting"nowdays,but the point is,drop the valve body and clean all valves and passageways and that usually cures 95% of all your problems.Hope this helps.Good luck. Marc :cool:

[Lindel]

Pete, it might be the vavle body, but I think it's more likely that the bands are way out of adjustment. If you've got another handy, swap it out, or get this one rebuilt, because if the bands are this far out, it has other issues.

Of course, I might be full of it, since I'm kind of guessing here.

JB, the 727 front pump doesn't turn in park, if you'll put it in neutral for about 30 seconds or so, then it'll shift into drive fine. You might try adding a bottle of STP oil treatment to the transmission, too. Believe it or not, it works, and the resident expert on the mailing list swears by it.

[Banks]

CJ,also wanted to say my local trans. man charges me $280 for a complete overhaul [12 month/12,000 warranty] if I bring him the tranny. Lindel,I know "jack s**t" about 727 trannys[400's for that matter]but I once asked about adjusting the bands on the 400's and was told there is none,they either work or they don't,but it sounds like CJ's is working because that is probably whats causing the "drag". Marc :cool:

[243]

No band adjustment on TH400

[Crazy_Jeepman]

Thanks guys, I appreciate the help and ideas. I think I will change the valve body, since this is not a big deal, and easier to do than swapping the trany. If it does not do it, I will swap it out, since I have spares anyhow. It is full of clean oil, linkages are adjusted and I have positive selection of the gears. It has non-abused 90,000 miles on it. I am the 3rd owner (twice now) of this rig. The trans still seems to shift fine in D, and L feels fine. Just can't understand the BRAKE EFFECT in 2nd and R :confused: :confused: Thanks again