Repair or rebiuld TH400?

[J. Rogers]

I've got a '74 Wag w/ 360 4v, A/C, P/S, P/B and a GM TH400. I'm having shift problems from 2nd to 3rd and slipping in reverse. The 2nd to 3rd upshift is practically becoming non-existent and the slipping in reverse is becoming the same way as 2nd to 3rd.

I've replaced fluid and filter but this hasn't helped. The old fliud was okay. No burned odor or fibers/filings.

Is repair a choice or does this require a rebiuld?

[River Beast]

Welcome to the Forum..
By all means I am no expert on trannys, butI do know that I have seen rebuild kits for the TH400 for less than $200. I may , in the future, tackle this myself.. but only in a situation such as yours...find a friend or somebody knowledgeable in the area and pick their brain apart.

Good luck... others will respond.. give it time...

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Todd
78 Wagoneer, "River Beast"
360/TH400/QT (maybe changin' QT soon to a Dana 18/20)
Dana 44's locked w/ 4.89's
39.50x15x15 Super Swamper TSL's on 15x12 Eagle 589's
7" SOA in front-7" Rear Shackle Inversion Mods
4" Skyjacker Softride
3" Trailmaster Bodylift
My FSJ site: http://www.geocities.com/spazz4life (http://www.geocities.com/spazz4life)
The "NEW" River Beast Preview site: <A HREF="http://home.earthlink.net/~tjnkk" TARGET=_blank>
http://home.earthlink.net/~tjnkk </A>
My E-mail: riverbeast@earthlink.net
"When approaching an intersection, remember...
the vehicle with the BIGGEST TIRES has the right of way..."

'93 3/4 ton 4x4 Suburban...a.k.a. "FSJ Hauler"

[J. Rogers]

Thanks. I'm not a Tranny Afficianado myself. I've got a good shop here in town that'll do the work. I just wanted to see if the guys on the forum had any ideas other than rebiulding.

I've learned to listen to what is said here. You guys are very helpful.

Again, thanks.

[trickc]

hey,just a shot in the dark but have you changed the shift modulator valve? big round thingy on passenger side with vac line that hooks into manifold,there is also a screw/hex nut up in there to adjust shifting.
fairly easy to change too.

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74 cherokee nt,4"lift,
33's,lockers,winch,custom bumpers,what else is there?

[J. Rogers]

Did that about a year ago. UR right, very easy and cheap, too. I've thought of that, but in my last adventure, the spark plugs in cyl's 6 & 8 were wet fouled from the tranny fliud. That's not happening now.

I guess I could've gotten water into the chamber somehow on my most recent ride. It's worth checking.

Thanks.

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Refu-JEEP
'74 Wagoneer 360 4v
TH400 Quadra Trac
Dana44 front & rear
No lift (yet)

[rawdave]

I was having a lot of slippage with my TF727. I went to one of those places that completely replace the tranny fluid(not just the little bit of fluid in the pan, but all of it) and now it shifts like a new one. These guys pull the cooler lines and hook up a big machine that basically lets the pump run all the old fluid out while it pulls new fluid from a resevoir in the machine.

worked for me, now no rebuild for a while anyway...

david

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87 Grand Wagoneer
TFI Upgrade
Thorley Headers

[J. Rogers]

Thanks. I put her in the shop this AM. I figured it's 26 - 27 yrs old, probably could use a rebuild. Maybe I'll get a good 10 yrs or so out of her now.

Thanks for the reply.

------------------
Refu-JEEP
'74 Wagoneer 360 4v
TH400 Quadra Trac
Dana44 front & rear
No lift (yet)

[ironroad29]

best thing to do is pull it and take a transmission course at the local community college and do it yourself ,classes are usually pretty cheap and they have them at night !! parts are cheap for the th400 so please don't let someone rip you off on the rebuild.

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"If a jeep can't take you there, maybe you should think twice about going"

[scotty]

another thing that helps is to lay out all the parts in cups,or on a big piece of paper so that you can lable what they are,and how they went back in.an auto tranny is just like an engine,theres not really any mystery to taking one apart an putting it back together just like you took it apart. check all hard parts for cracks and obvious wear.make sure t the clutches/bands all have friction material left on them.if youve got a rebuild kit,youll be replacing them,but they can tell you why it quit working.

i know the guy that works at a local tranny shop,and he was an imense help when i decided to rebuild my 727 after filling it with muddy,silty water and it would no longer move. i took him some clutches,steels,bands and the front pump for him to check out.all were good.i also picked his brain on other things while i had it apart.

the valvebody is alittle tricky to take apart,clean,and get back together since there are so many parts-little balls,springs,things htat slide back and forth- a good shop manual helps quite a bit,too.

other than that,the only real tough part was getting all the little tabs ligned up on the clutches to get the drums back together-i had it in and out prolly 10 times before i was confident that the forward drum was seated all the way down like it was supposed to be.

i also had my torque convertor cut apart.it was full of mud silt and general filth.yuck! i bought a new one with a drain plug.

i didnt even buy a rebuild kit-all i did was take it apart,thouroughly clean it and put it back together and it works,tho it does slip alitte in reverse-may not have the band adjusted correctly.

having said all that,is is a fair amount of work,and a big disappointment to remove,rebuild,replace a tranny and still not move. someone who knows what they are doing can "blueprint" it and check things as theyre going,much like rebuilding an engine or carb. its also nice to have a warranty,which you willnot have if you do it yourself. you can save a fair amount of $$ by pulling it yourself and delivering it to the tranny shop.

for me it wasnt a real big deal if it still didnt work,i wanted to see what would happen,but in alot of cases,it may be worth the $$ to have a pro do it and be gauranteed that it will work and have that warranty http://www.ifsja.org/ubb/smile.gif

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scott
85 grand wagoneer
258 with motorcraft 2bbl/904/twin stick dana 300/dana 44/welded amc 20
38x15.5 gumbo mudders
snorkel/dual batteries/onboard air/"custom" convertable
3 inch body lift/mostly stock suspension/"modified" fender openings
custom front/rear bumpers and brushgaurd

T18/dana-spicer 18 with drum E brake and PTO,and offset dana 44 swap very soon
BIG tow truck PTO winch and full roll cage install shortly thereafter
searching for jeep 4.0 six engine

now we can do some 'wheelin!

[Veepster]

I have been thinking about rebuilding mine myself also....I saw a video in the Summit catalog for $49 titled "how to rebuild a TH400"......one of my next projects!........

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Peace.............BartG

the Green Flash!
360ci
Custom 4v TBI
Edelbrock Performer Manifold
TH400, QT with low
4" skyjacker Rancho 9000's
33x12.50 BFG KO's 8" American Racing Baja Rims
Thorley headers, 3" exhaust, Dyno Max
Infiniti power leather seats
Custom billet shift knob by Millerluck
50%Luxury Car, 50%Tractor
http://www.teamgodspeed.com

[River Beast]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Veepster:
I have been thinking about rebuilding mine myself also....I saw a video in the Summit catalog for $49 titled "how to rebuild a TH400"......one of my next projects!........

<HR></BLOCKQUOTE>

I may be heading up to LA this weekend... via Carlsbad....HINT, HINT!!! I may have "something" for you if you are still interested...E-mail me...



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Todd
78 Wagoneer, "River Beast"
360/TH400/QT (maybe changin' QT soon to a Dana 18/20)
Dana 44's locked w/ 4.89's
39.50x15x15 Super Swamper TSL's on 15x12 Eagle 589's
7" SOA in front-7" Rear Shackle Inversion Mods
4" Skyjacker Softride
3" Trailmaster Bodylift
My FSJ site: http://www.geocities.com/spazz4life (http://www.geocities.com/spazz4life)
The "NEW" River Beast Preview site: <A HREF="http://home.earthlink.net/~tjnkk" TARGET=_blank>
http://home.earthlink.net/~tjnkk </A>
My E-mail: riverbeast@earthlink.net
"When approaching an intersection, remember...
the vehicle with the BIGGEST TIRES has the right of way..."

'93 3/4 ton 4x4 Suburban...a.k.a. "FSJ Hauler"