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Discussion Starter #1
Hi there

Having problems with a non-lockup th350...

Drops out of gear and only appears to be using 2 gears, don't know if it's skipping 1st, 2nd or not going into 3rd as this is a problem had since I bought the car. It's on a 400ci smallblock and the previous owner assumed it was running a 2 speed powerglide (as the original would have had)

Anyway i've ID'd the box as definitely a 350, with a 13 bolt pattern on the pan and the triangular corner missing. Not a 250 as there is no band adjuster by the cooler lines, and it's a non-lockup (no electrical connector on drivers side of box)

Put a new vacuum modulator on it last week, which is adjustable (although haven't messed with it yet) and it makes it shift smoother, but the problems still exist

Any ideas on what could cause the problems? Governor perhaps?

I don't know much about auto boxes and might just take it somewhere to be fixed, but need it done before Old Warden

Does anyone know of a good specialist in the SE area, perhaps in and oround London or Dartford/Gravesend way? Someone who could drive it and put their finger on it?

I tried Automatic Gearbox Specialists near Gravesend clock tower, they reckoned it probably needs a rebuild, but i'm not so sure


Cheers

Dave
 

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Discussion Starter #3
Lovely but would he speak to someone as lowly as me? hehehe :p

I take it he's up for giving a bit of advice, I know he's a bit far for me to drag the car to
 

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Andy Frost is one of the most approachable racers I have ever met. I am sure he would advise you over the phone He runs his transmission business out of Wolverhampton, this is the website
http://www.redvictor1racing.co.uk/ follow the 'Penn Autos' Link

Tony

Lovely but would he speak to someone as lowly as me? hehehe :p

I take it he's up for giving a bit of advice, I know he's a bit far for me to drag the car to
 

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have you got the correct shifter in the car and that its adjusted correctly? if the fella thought it was a 2spd can you shift into all gears?

easy to tell because you should be able to go through PRN12(3 if a TH350) so you know what gear is missing - would have thought it was 3rd it wasnt getting if it was a 350.
 

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Lovely but would he speak to someone as lowly as me? hehehe :p

I take it he's up for giving a bit of advice, I know he's a bit far for me to drag the car to
No-one is lowly to me fella.I'm from Wolverhampton..:D
Give me a call to tell me the exact symptoms you have and we can see if the problem is outside or inside..
Thanks for giving my number out Tony..:tup:
 

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Discussion Starter #7 (Edited)
Thanks guys.... Andy i'll give you a ring tomorrow if that's alright!

Well in terms of the linkage, it may be a problem there... looking from underneath it seems it might have had a floor shifter at some point, theres a patch about the right size

It's a column shifter... I had an 80's Chevy blazer (unmodified) that showed "N" as drive, obviously from a worn/stretched linkage on the column, but no problems on the gears so accepted it (was a project that became a lemon in the end!)

When i originally got the Impala I figured it was a powerglide but with the same issue

Obviously since I got underneath it isn't... now i'm guessing it may be that although it seems to select "D" in the "N" position it may well be in drive but perhaps not all the way in? perhaps a bump in the road knocks it back out? However...

From park I go Park, Neutral Drive... pops into drive... works well (most of the time from cold changes up a gear, sometimes not? Although seems no problem with the pressure line, it has popped off the carb end before but now i've got it it clamped on)

If it doesn't shift up I can push the column shifter up a notch into neutral, let off the gas, pull it down into drive and it selects the right gear for the speed i'm doing... same if it drops out of gear

I can also blip the gas when it drops out of gear and it will go back in... similar to kicking it down (and trust me the kick down works a treat?) but then it'll only hold it in he same gear for about 5 seconds, even on the motorway at 60 just above 2000 revs :wacky:

Worst is when i'm in supposedly first, doing just about 30, it shifts up then i reach some traffic or need to slow down and let off and around 1000 revs it just drops out and seems to coast... no good for blipping the gas in case it grabs the gear and I fly into the bloke in front! :shocked: Don't get me wrong I know it's supposed to drop down at a certain point but but when I go back on the gas it won't shift back up AT ALL unless I go into neutral and back into drive

Spoke to Paul burnham a few months ago as I wanted the powerglide replaced and he suggested some other boxes, 350 included, which I actually have... so probably no need to upgrade to a 3 speed with overdive... just want to know if it needs a rebuild or it might be something simpler that I can do myself

I prefer to get under my cars and fix stuff myself as I get much more satisfaction from it, but growing up doing manual geared old fords (mk1 escort was my first car, mk1 cortina gt 2nd) hasn't really prepared me for the yank automatics... anything else i'm fine with so i suppode it's a great learnign curve! :tup:

However Burnham's have done work for me before and I know it is of the HIGHEST quality and he's also a top man (built my old man's '34 coupe for a start)

Any other suggestions before I get on the phone are much appreciated

Cheers guys


Dave
 

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Thanks guys.... Andy i'll give you a ring tomorrow if that's alright!

Well in terms of the linkage, it may be a problem there... looking from underneath it seems it might have had a floor shifter at some point, theres a patch about the right size

It's a column shifter... I had an 80's Chevy blazer (unmodified) that showed "N" as drive, obviously from a worn/stretched linkage on the column, but no problems on the gears so accepted it (was a project that became a lemon in the end!)

When i originally got the Impala I figured it was a powerglide but with the same issue

Obviously since I got underneath it isn't... now i'm guessing it may be that although it seems to select "D" in the "N" position it may well be in drive but perhaps not all the way in? perhaps a bump in the road knocks it back out? However...

From park I go Park, Neutral Drive... pops into drive... works well (most of the time from cold changes up a gear, sometimes not? Although seems no problem with the pressure line, it has popped off the carb end before but now i've got it it clamped on)

If it doesn't shift up I can push the column shifter up a notch into neutral, let off the gas, pull it down into drive and it selects the right gear for the speed i'm doing... same if it drops out of gear

I can also blip the gas when it drops out of gear and it will go back in... similar to kicking it down (and trust me the kick down works a treat?) but then it'll only hold it in he same gear for about 5 seconds, even on the motorway at 60 just above 2000 revs :wacky:

Worst is when i'm in supposedly first, doing just about 30, it shifts up then i reach some traffic or need to slow down and let off and around 1000 revs it just drops out and seems to coast... no good for blipping the gas in case it grabs the gear and I fly into the bloke in front! :shocked: Don't get me wrong I know it's supposed to drop down at a certain point but but when I go back on the gas it won't shift back up AT ALL unless I go into neutral and back into drive

Spoke to Paul burnham a few months ago as I wanted the powerglide replaced and he suggested some other boxes, 350 included, which I actually have... so probably no need to upgrade to a 3 speed with overdive... just want to know if it needs a rebuild or it might be something simpler that I can do myself

I prefer to get under my cars and fix stuff myself as I get much more satisfaction from it, but growing up doing manual geared old fords (mk1 escort was my first car, mk1 cortina gt 2nd) hasn't really prepared me for the yank automatics... anything else i'm fine with so i suppode it's a great learnign curve! :tup:

However Burnham's have done work for me before and I know it is of the HIGHEST quality and he's also a top man (built my old man's '34 coupe for a start)

Any other suggestions before I get on the phone are much appreciated

Cheers guys

Dave
sounds modulator or governer related. Call me and i'll walk you through some checks..
 
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