GM B-Body Forum, 77-79 Caprice/Impala Forum

Join Now If Your A 1977- 1979 Caprice or Impala owner or other GM B-Body owner!!!
Like us on Facebook https://www.facebook.com/BBodyForum?ref=hl

Join the forum, it's quick and easy

GM B-Body Forum, 77-79 Caprice/Impala Forum

Join Now If Your A 1977- 1979 Caprice or Impala owner or other GM B-Body owner!!!
Like us on Facebook https://www.facebook.com/BBodyForum?ref=hl

GM B-Body Forum, 77-79 Caprice/Impala Forum

Would you like to react to this message? Create an account in a few clicks or log in to continue.
GM B-Body Forum, 77-79 Caprice/Impala Forum

A forum for the owners and enthusiasts of General Motors B-Bodies from 1977-1990, but dedicated to the owners of 1977-1979 Impalas and Caprices. Join up now!


5 posters

    Th200 to TH350 swap

    HeavyChevy77
    HeavyChevy77
    Freshman Member (Tier 3)
    Freshman Member (Tier 3)
    10th Year Anniversary
    10 years of being a member on our forum!


    Posts : 243
    Join date : 2013-07-03
    Age : 31
    Location : San Diego, Ca

    Th200 to TH350 swap Empty Th200 to TH350 swap

    Post  HeavyChevy77 Sun Mar 22, 2015 12:43 pm

    So my th200 feels like its on its way out. Starting to feel a little slipping when im getting on it, this whole time i thought i had a th350 and got the pan to change the fluid, but checking the pan to some pics on the net i find out its the th200 which people say (including my school transmission teacher) are piece of s#!+ but ive been pushing this trans hard(seems theres a mustang/charger/challenger wanting to get took on every corner) for a while now and is still solid.
    i was gonna do a 2004-r swap but i gotta cut the drive shaft so i was thinking the th350
    those are fairly cheap and hear its direct swap just need a detent cable, torque coverter,maybe a bracket for the carb. Will my flywheel be ok? 
    I hoping someone post with their swap experiances
    Myloth
    Myloth
    Moderator
    Moderator
    Helpful and Responsive Member!
    Very active with responding and helping other members with questions and concerns.
    5th Year Anniversary
    Celebrating 5 years of being our member!


    Posts : 638
    Join date : 2014-06-09
    Location : At the base of the Mountain (NY) Adirondacks

    Th200 to TH350 swap Empty Re: Th200 to TH350 swap

    Post  Myloth Mon Mar 23, 2015 3:45 pm

    You heard right the thm200 is low duty trans that is disposable.  The 2004r does require a flexplate from  say a

    80s MonteCarlo anything that came with the 2004r should be under 50 from a yard for that flexpate. The

    only real challenge is you have to move the transmission mount location one way or another with some swap like

    a th350 to 2004r in your case you might be ok as they are based on the same design GM just beefed up the

    2004r when they made it .(probably added the intermediate clutch pack they took out of the thm200 lol)
    HeavyChevy77
    HeavyChevy77
    Freshman Member (Tier 3)
    Freshman Member (Tier 3)
    10th Year Anniversary
    10 years of being a member on our forum!


    Posts : 243
    Join date : 2013-07-03
    Age : 31
    Location : San Diego, Ca

    Th200 to TH350 swap Empty Re: Th200 to TH350 swap

    Post  HeavyChevy77 Mon Mar 23, 2015 5:35 pm

    i wanted the 4 speed but if i can get a th350 cheap for piece of mind it wont break on me.
    But i have the thm200 and want to put a th350
    Sweet Seventy9
    Sweet Seventy9
    *Senior Moderator*
    *Senior Moderator*
    Helpful and Responsive Member!
    Very active with responding and helping other members with questions and concerns.
    10th Year Anniversary
    10 years of being a member on our forum!


    Posts : 973
    Join date : 2013-11-03
    Location : Upstate NY

    Th200 to TH350 swap Empty Re: Th200 to TH350 swap

    Post  Sweet Seventy9 Mon Mar 23, 2015 6:05 pm

    Unfortunately, nothing from the th200 can be used. You need the th350 complete with the torque converter, kick down cable, etc.
    The flex plate will be re-used though.
    It's a straight in swap except for possibly moving the crossmember to accommodate the mount for the th350.
    I don't think any alterations to the driveshaft will be required.
    HeavyChevy77
    HeavyChevy77
    Freshman Member (Tier 3)
    Freshman Member (Tier 3)
    10th Year Anniversary
    10 years of being a member on our forum!


    Posts : 243
    Join date : 2013-07-03
    Age : 31
    Location : San Diego, Ca

    Th200 to TH350 swap Empty Re: Th200 to TH350 swap

    Post  HeavyChevy77 Mon Mar 23, 2015 6:21 pm

    thanx bro 
    ive beeb meaning to do a trans service on it i had bought a filter and pan (for the th350 tho) should i just buy the filter and gasket clean the pan and do it or should i not waste good atf lol..
    Sweet Seventy9
    Sweet Seventy9
    *Senior Moderator*
    *Senior Moderator*
    Helpful and Responsive Member!
    Very active with responding and helping other members with questions and concerns.
    10th Year Anniversary
    10 years of being a member on our forum!


    Posts : 973
    Join date : 2013-11-03
    Location : Upstate NY

    Th200 to TH350 swap Empty Re: Th200 to TH350 swap

    Post  Sweet Seventy9 Mon Mar 23, 2015 6:30 pm

    Well, it never hurts to change the fluid and filter.

    When you're all set to do the swap, you should retire the th200 in a blaze of glory!  I know they'll withstand a 305 with a 150 shot of nitrous.  I wonder what a 5000 rpm neutral drop would do to one, lol?

















    lol, I'm not serious! Laughing Laughing Laughing Laughing
    HeavyChevy77
    HeavyChevy77
    Freshman Member (Tier 3)
    Freshman Member (Tier 3)
    10th Year Anniversary
    10 years of being a member on our forum!


    Posts : 243
    Join date : 2013-07-03
    Age : 31
    Location : San Diego, Ca

    Th200 to TH350 swap Empty Re: Th200 to TH350 swap

    Post  HeavyChevy77 Mon Mar 23, 2015 7:01 pm

    Aw man u had me goin ..pondering of possiblities hah but the work that trans has put in, pissing/surprising people off the line  and leaving em behind, it will retire with a chip on its 
    shoulder but maybe some somkey burnouts/donuts will do..Oh what if i try that 180 reverse manuver where u punch it in reverse and whip the steering wheel to spin 180 and put that bi+*# in drive and smash the pedal lol..now if i can just find a spot
    Sweet Seventy9
    Sweet Seventy9
    *Senior Moderator*
    *Senior Moderator*
    Helpful and Responsive Member!
    Very active with responding and helping other members with questions and concerns.
    10th Year Anniversary
    10 years of being a member on our forum!


    Posts : 973
    Join date : 2013-11-03
    Location : Upstate NY

    Th200 to TH350 swap Empty Re: Th200 to TH350 swap

    Post  Sweet Seventy9 Mon Mar 23, 2015 7:14 pm

    Walmart parking lot? Very Happy
    solo79
    solo79
    *Senior Moderator*
    *Senior Moderator*
    10th Year Anniversary
    10 years of being a member on our forum!


    Posts : 458
    Join date : 2013-02-06
    Location : Kentucky

    Th200 to TH350 swap Empty Re: Th200 to TH350 swap

    Post  solo79 Mon Mar 23, 2015 7:28 pm

    I seem to recall my first Caprice had the TH200 and went out 2 weeks after I bought the car. We salvaged my Father's short tail TH350 out of his rusted out 72 GMC Sprint and it bolted right in the Caprice with zero modification. I remember having them side by side on the concrete drive as we pondered if it would work or not. We stuck it up in there and bolted all up and I sold that car 10 years later transmission still working. I don't remember doing anything with the cross member. As Sweet already mentioned, nothing from the 200 was reused, well except the 9/16" housing mounting bolts. I did reuse my same flywheel. The TH350 is not good for interstate speeds if you have low gears as my 82 Trans Am does and cranks 2500 RPM at 60 mph. You'll cook the engine at 70+. I don't recall what gears my first Caprice had, but it would cruise at 70 at a nice RPM and didn't sound like it was screaming.
    HeavyChevy77
    HeavyChevy77
    Freshman Member (Tier 3)
    Freshman Member (Tier 3)
    10th Year Anniversary
    10 years of being a member on our forum!


    Posts : 243
    Join date : 2013-07-03
    Age : 31
    Location : San Diego, Ca

    Th200 to TH350 swap Empty Re: Th200 to TH350 swap

    Post  HeavyChevy77 Mon Mar 23, 2015 8:16 pm

    *sweet if only the didnt have all those lamp posts ..lol 
    thanks solo79 
    i have the 2.56 gears (i think) but have the impala rear waiting to swap (wondering if i need to cut the shaft for the axle swap but the axles are the same depth from u joint strap to diff cover flange and the same LowerTrailingArm length) the axle has 3.08 gears
    Myloth
    Myloth
    Moderator
    Moderator
    Helpful and Responsive Member!
    Very active with responding and helping other members with questions and concerns.
    5th Year Anniversary
    Celebrating 5 years of being our member!


    Posts : 638
    Join date : 2014-06-09
    Location : At the base of the Mountain (NY) Adirondacks

    Th200 to TH350 swap Empty Re: Th200 to TH350 swap

    Post  Myloth Sat Mar 28, 2015 12:15 pm

    Just remember unless you add a line pressure override that TV cable's setting is crucial as on the 2004r it controls

    line pressure for the transmission. There are several videos and write ups on the internet about it. The override if

    you want to modify the valve body it's cheap otherwise a valve body with fixed pressure is something like this.


    http://www.jakesperformance.com/200-4R_Components.html

    terry cronk
    terry cronk
    Freshman Member (Tier 3)
    Freshman Member (Tier 3)
    5th Year Anniversary
    Celebrating 5 years of being our member!


    Posts : 249
    Join date : 2015-08-19
    Age : 76
    Location : Mid-Michigan

    Th200 to TH350 swap Empty 200 to 350 trans.

    Post  terry cronk Thu Nov 19, 2015 8:18 pm

    A 350 trans will go right in for the 200 replacement.
    HeavyChevy77
    HeavyChevy77
    Freshman Member (Tier 3)
    Freshman Member (Tier 3)
    10th Year Anniversary
    10 years of being a member on our forum!


    Posts : 243
    Join date : 2013-07-03
    Age : 31
    Location : San Diego, Ca

    Th200 to TH350 swap Empty Re: Th200 to TH350 swap

    Post  HeavyChevy77 Fri Oct 19, 2018 3:00 pm

    Th200 to TH350 swap 20181011
    Th200 to TH350 swap 20181012
    Th200 to TH350 swap 20181013

    So from my last post here my th200 was showing its age fast foward 3 years and she finally have gave out reverse was going out and then it only had first gear pulling off the freeway few weeks ago. Pulling the drain plug showed metal shavings (paper fiction clutches gone?) Well I foind a th350 for $200 conplete from the tq conver to the yoke and dipstick to the pan...I think I got the deal of the year.. Came outta a 79 camaro with a inline 6 had driven it around on the trans before removing.
    Everthing went in smooth same mount/driveshaft used have got a flexplate cover yet and the trans lines were tweaked by hand slightly totl thread in nicely..other than that smooth install changed a pipe plug on the intake to a nipple to feed the modulator vaccum. Prior to replacing car drive drove good had to give a little extra gas to get the 1-2 shift but felt snappy firm..
    Now I kinda sounds like poo sluggish off the line if i drive like an old man it goes smooth but tip more the half throttle feels like it stumbles sputter ..manually shifting feels better but not strong as it could be.
    Checked my modulator vacuum line ends and replaced some dried hoses ( no atf fluid in the lines) but still ehh on the performance.
    Bought a shift kit & modulator for a 77 vette ive yet to install maybe thats the difference as the th200 had a shift kit in it.
    I never messed with the carb prior to replacement just dropped the tranny and slapped in the other one.
    I'm using a vacuum port on the manifold for the modulator but I doubt if using the manifold port on the back of the qjet would make a difference on the modulator function.
    Any idea would be appriciated. Thanx guys
    HeavyChevy77
    HeavyChevy77
    Freshman Member (Tier 3)
    Freshman Member (Tier 3)
    10th Year Anniversary
    10 years of being a member on our forum!


    Posts : 243
    Join date : 2013-07-03
    Age : 31
    Location : San Diego, Ca

    Th200 to TH350 swap Empty Re: Th200 to TH350 swap

    Post  HeavyChevy77 Sat Oct 20, 2018 12:29 pm

    Replaced the modulator felt a little better
    Tested the old one held vacuum fine.

    Sponsored content


    Th200 to TH350 swap Empty Re: Th200 to TH350 swap

    Post  Sponsored content


      Current date/time is Fri Apr 26, 2024 6:59 am