Automatic transmission advise needed...Bad

[TooRisky]

I have a 1977 Full Sized Jeep Cherokee, it has a very strong 401, backed with a TH400 which till yesterday was damn bullet proof....

I went up onto Huckleberry ridge from Tacoma with absolulty no problems, no slipping and actualy to much power for the wet forest service trials on the up side....Now I had heated brakes comming down the down side before and decided the drop the tranny into 1st and just simply walk it off the ridge nice and easy....

I got to the bottom and did my buisness and headed back up the FS road and found I did not have drive, only 1st and 2nd....We crossed over the pass into the low land and camped and I shut her down, thinking I was low on tranny fluid and would pick some up on the way out...

Well the problem was there in the morning and did not travel on the hiway more than a 100 yards before puling off and having my partner go to the nearest town and get some tranny fluid for my age of tranny...

I in turn looked into the problem, I had tranny fluid showing but was a quart low, did not smell burnt and was a good color pink. My partner came back with the correct AFT and filled the tranny up...

I still did not have drive...I slowly walked it down to Greenwater and was given permission to leave it there till I can come get it with the Burb. and trailer on Sat.

The question is what could be the problem...there was not any pre problems like slipping ect, the fluid did not smell of urnt tranny...and it revs up like maybe the linkage was F'ed up but I still had, 1st, possible 2nd, neutral, reverse, and park.

I am to go get her early Saturday...any Ideas...Before the huge tranny shop bills....

Please only tranny guys in the know....It is a TH400 hydromatic

 

[crash2]

First thing--pull the pan and look in the bottom of the pan for any metal flake or buildup. Just checking the fluid isn't enough becuase you can have something fail and not burn the fluid. I am going to assume its simply not shifting into drive because otherwise it would flare up when trying to go into third. To me it sounds like a valve in the valve body hanging up. Thats typical of an "all of a sudden" issue even more with a tranny that was working flawless,,

 

[TooRisky]

Thanks Crash...I hate going into a shop with out an idea and letting them know this fact...I will pass this on and hopefully not get hosed...This is my biggest fear, cause I know the tranny is super strong and there were no tell tale signs of any failure....

 

[Skid Mark]

One more thing to check is the vacume modulator on the trans. Deaccelerating using the transmission creates higher vacume loads and is useually when the diophrams give out and it would cause simualer shifting problems

Add it to the list its a cheep fix :awesomework:

 

[Binder]

The vacuum hose fell off the modulator or your shifter linkage is screwed up.

 

[crash2]

Thanks Crash...I hate going into a shop with out an idea and letting them know this fact...I will pass this on and hopefully not get hosed...This is my biggest fear, cause I know the tranny is super strong and there were no tell tale signs of any failure....

It takes a spec of crap to hold a valve up. A vacuum modulator will typicly not get a 1-2 shift--or it will be VERY late and very hard....

 

[WHITE TRASH1]

It takes a spec of crap to hold a valve up. A vacuum modulator will typicly not get a 1-2 shift--or it will be VERY late and very hard....

Word... Pull the valvebody and clean all the valves and passages mil spec. It is probably overdue for a filter kit and flush anyway so see this as your mandatory reminder. :redneck:

 

[TooRisky]

I want to thank each and everyone for your sage advise...When it comes to trannies I have no clue, do to this is my first ever tranny problem in my 47 years on this planet...Knock on wood.

Again thanks for the hope it will be a cheap fix and ideas to present to the shop, so I dont look like a complete moron with a fat wallet.

Steve

 

[crash2]

I want to thank each and everyone for your sage advise...When it comes to trannies I have no clue, do to this is my first ever tranny problem in my 47 years on this planet...Knock on wood.

Again thanks for the hope it will be a cheap fix and ideas to present to the shop, so I dont look like a complete moron with a fat wallet.

Steve

Let us know what the fix is steve--as I am always interested in the end of the story :awesomework:

 

[TooRisky]

Well there is a very reputable transmission shop called "Parkland Transmission", I talked to Bob and he said it is probably an easy fix...Either a vacuum line came off or is cracked and to fix it myself (cool)...or that the governor is stripped and the unit needs replacing ($60.00)...

I think what ever I do the tranny needs to have the filter changed and flushed the tranny flushed ($109).

So if the planets are all aligned right I may get off lucky money wise.

I will let you all know the out come.

Steve

 

[WHITE TRASH1]

Don't fall for the flush and fill... You can grab a can of cooler flush and run it through the trans cooler and swap the filter and oil out for under $40 total... So unless you're pressed for time just do it yourself.

 

[crash2]

Don't fall for the flush and fill... You can grab a can of cooler flush and run it through the trans cooler and swap the filter and oil out for under $40 total... So unless you're pressed for time just do it yourself.

I dissagree. A flush will get all the fluid. I don't try to sell those "flush's" but when it comes to tranny's I do... You have to remember that when you pull a pan your only getting 1/2 of the fluid out of a trans.

 

[TooRisky]

I am with Crash on this one, I dont know the tranny maintance before I bought it, and it has not been done in my ownership, so it is getting done. Complete flush and filter kit...

 

[Binder]

Have you bothered to check the modulator line yet? Could have been fixed by now and you could be wheeling it right now.

 

[Spanaway Mudder]

Steve... If all else fails.. I know where a nice T400 with X-case is sitting for sale.. Pm me if interested:awesomework:

 

[CHOP SHOP]

I dissagree. A flush will get all the fluid. I don't try to sell those "flush's" but when it comes to tranny's I do... You have to remember that when you pull a pan your only getting 1/2 of the fluid out of a trans.

Don't fall for the flush and fill... You can grab a can of cooler flush and run it through the trans cooler and swap the filter and oil out for under $40 total... So unless you're pressed for time just do it yourself.

I am with Crash on this one, I dont know the tranny maintance before I bought it, and it has not been done in my ownership, so it is getting done. Complete flush and filter kit...

I have seen so many positive thinkers change tranny fluid hoping to magicly fix a tranny haha::haha::haha.

Usually just costs them about 40 bucks worth of a filter and oil to realize it didnt do anything but give them a five gallon bucket of old oil to get rid of!!

Good luck with that flush!:awesomework:

 

[crash2]

I have seen so many positive thinkers change tranny fluid hoping to magicly fix a tranny haha::haha::haha.

Usually just costs them about 40 bucks worth of a filter and oil to realize it didnt do anything but give them a five gallon bucket of old oil to get rid of!!

Good luck with that flush!:awesomework:

I forgot you work in the industry and are around this stuff all the time :haha::haha:

Its about preventative maintenance and not to be used as a "fix"

 

[TooRisky]

Well happy ending here...It was a worn through vacuum hose, so I picked up some hose and all was good....simple things that make a huge difference huh. Might be a good thing to put in the old tool bag about 3-4feet of vacuum hose, never know when or how far from help you will be.

I am to go in and get her flushed/filter kit, looks like the pan is leaking abit so take care of all of that in one trip.

Thanks all, you all were a wealth of info...

Steve

PS is the vacuum leaveing or entering the transmission..???

 

[crash2]

Well happy ending here...It was a worn through vacuum hose, so I picked up some hose and all was good....simple things that make a huge difference huh. Might be a good thing to put in the old tool bag about 3-4feet of vacuum hose, never know when or how far from help you will be.

I am to go in and get her flushed/filter kit, looks like the pan is leaking abit so take care of all of that in one trip.

Thanks all, you all were a wealth of info...

Steve

PS is the vacuum leaveing or entering the transmission..???

vacuum comes from the motor. Interesting--typicly you don't even get it into 2nd...

 

[CHOP SHOP]

I forgot you work in the industry and are around this stuff all the time :haha::haha:

Its about preventative maintenance and not to be used as a "fix"

Looks like changin the fluid would have done nothin for him, huh?
Ive killed more gm autos than you can imagine.:kissmyass:

vacuum comes from the motor. Interesting--typicly you don't even get it into 2nd...

Yer years in the "industry" and this surprises you?