Everything you ever wanted to know about a TH400 swap..I think
12-22-2001, 10:47 PM
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Everything you ever wanted to know about a TH400 swap..I think Well I said that I was going to do a writeup of my experience swapping a TH400 for my T-56 in my 99 T/A. I also put in a moser 9" along with this swap and I would recommend anyone doing this swap have a good strong rearend I.E. 12-bolt or 9". I mean just shifting from park to reverse or 1st on this tranny shocks the driveline. I dont believe that a stock 10-bolt would live very long behind a th400 or th350.
First thing you're going to need to do is get a TH400 built. I went with a TH400 with reverse pattern valvebody and a transbrake. I also opted to swap out the stock 2.48 first gear ratio in the tranny for a slightly lower 2.75 first gear. The cost of swapping the first gear out was $480. I did this because the motor I'm planning on building for the car I will be running a big shot of nitrous and by going with a 2.75 first gear I could go with a little taller gear in the rear and not lose a whole lot in the 60'. I bought the tranny from a local shop here in Florida. The guy I bought it from builds trannies for 6 second dragsters so I figured that he would be able to build a tranny that would hold up to what I'm planning on throwing at it. The total cost of the tranny was 1450. I did look at getting the whole entire kit from yank. However two friends of mine purchased trannies from yank and had trouble with it. They had their trannies rebuilt by the guy who built mine and have had no trouble since. I personally think that the yank kit is a little bit over priced at over 3000 dollars. This is in no way a flame against yank I think yank makes a great converter and has great service. When I buy another converter for the new motor I will definately look at yanks.
With that being said the next thing you will need is a converter. Yanks kit includes one of their 9" thruster converters I believe. I went with a JW 10" converter. The same one GeorgeC is using and cutting 1.3x 60's with. The converter cost me around $460 with shipping. When you order a converter you may or may not need to get a crank pilot sleeve. When I went to install the tranny in the car for the first time the crank pilot on the converter was about 1/4" away from going into the crankshaft. I called JW and told them the problem and they sent me out a beautifully machined piece that slides right over the converter and extends the crank pilot to make it fit into the crank perfectly. They didn't charge me for this piece at all and everyone I talked to there was very helpful.
Next thing you will need to do is decide where to get a tranny crossmember from. Yank sells one that you can use your stock tq arm with for around $250. I talked to Brett at BMR and he made me one that I'm pretty sure he will be selling in the near future. The piece he sent me was awesome and fit great. It came powder coated black. I wont go into how much Brett charged me for this piece because I'm not sure how much he will be selling them for. I am almost positive that it will be a very good price and probably less than yanks. If you do go this route you will need to figure out something to do with your torque arm. The only options I know of that dont bolt up to the stock tranny are the spohn tq arm that mounts to where the tunnel brace mounts. Or the BMR trak-pak or extreme duty torque arm that mount on a crossmember welded in between their boxed SFC's. This is the tq arm I got.
Next you will need a shifter. There are alot of shifters that I have seen used and personally in my opinion none of them look as good as the hammer that I used. I think it looks the most factory and you dont have to hack up your console at all to make it fit. If you're swapping from an A4 to a TH400 you will need to get the upper console out of a 6speed car that has the leather shift boot. I was already swapping from a T-56 so I already had the console. To install the shifter I went to home depot and bought a piece of aluminum that was 2" x 24" x 1/4" I meausured the hole in the floorboard that the old shifter was in and cut two pieces from the aluminum to that length and mounted them in the center of the hole. I then placed the shifter on them to mark the holes the shifter would mount on. When I mounted the shifter I used some washers on the rear bolts to raise it up just a bit because when I installed the console it was hitting the shifter if I didn't use the spacers. I marked the hole for the shifter cable in the floorboard and then drilled it out. So after you get the shifter installed you will have two approximately 2" spaces on either side of the shifter so what I did was get some very thin 16ga aluminum and cut it out to shape and used the stock holes that mounted the old shifter and put them in. I then got some high temp silicone sealant and sealed all the gaps up from underneath the car. If you're swapping from a 6 speed car you will need to run the wires that were on your clutch switch over to the neutral safety switch on whatever shifter you buy so that the car will start only when the tranny is in park. I havent hooked up my backup lights yet but I'm sure it's not hard to figure out I just havent gotten around to it yet. Here are some pics of the shifter install
When you go to put the tranny up in the car it's best if you cut off the two ears that come off the side of the tranny for clearence of any headers you may put on the car. This pic shows where I cut
You will need to get a new driveshaft made. I bought my rear end and driveshaft from a friend who already had a th400 in his car so I didn't have to do this. I'm going to be purchasing a driveshaft from dennys soon however as my driveshaft is pretty out of balance right now.
When you bolt the tranny up to the block all the holes except one on the very top of the th400 will be used. this is 5 out of 6 bolts which should be plenty as long as they are torqued preperly.
For the tranny cooler iI bought a TCI cooler from jegs. It already has 6an line fittings right on the cooler. To do it this way you need the tranny cooler, 15 feet of -6an line, (2) 90deg -6an swivels, (2) 45deg -6an swivels, (2) -6an to 3/8 NPT fittings, and (2) -6an to -6an flare unions. The -6an to NPT fittings go into the tranny and the 45deg swivels go onto those. from there they go to the cooler which I mounted in front of my ac condenser on the passenger side of the car. On the tranny cooler you'll need the 90deg swivels and the -6an flare unions.
For the tranny dipstick I purchased one from lokar that was for a TH400 and was a firewall mount. This is a little bit hard to get to because it mounts WAYYYY on the back of the firewall on the car as it's only 2 feet long but it's not too bad.
After you get the tranny bolted in and shifter cable hooked up it's time to deal with the speed sensor. At the present time I havent hooked mine up yet so I dont know if thge way I did it will work or not. When I get around to doing it I'll post on how it turns out. But I can say that the way I did it is WAYYY cheaper than buying the sensor kit from yank for $250.
After all was said and done It took about 5 hours to get all the work done. and the car on the road. First impressions on the tranny are that it shifts HARD. Just putting the car into reverse or first shocks the tires and the whole car jerks. On the road it shifts great nice and crisp and exactly when I want it to. I love the hammer shifters ratchet action. It takes a little more getting used to than the 6speed as you have to remember what gear you're in and to remember to put it into first when you come to a stop. After driving this setup I wouldn't think about going back to the 6speed. My car is very lightly modded the way it sits now all I have done is a whisper lid/maf ends, and an exhaust cutout. before the TH400 with the 6speed I ran a best of 12.74 @ 110. With the th400 and 9" I was able to pull a 12.71 @ 107 the first time out with the car. That was on nittos and launching off the footbrake not the transbrake. I'd say the way the car sits a 12.5x is possible if i can cut a good 60'. The driveline is definately eating up some power I'm getting it dynoed again soon so I can see exactly how much.
Well that's it. Sorry for such a long post but since everyone was asking about this swap so often and with so many different posts I figured I'd try and put it all together in one. I'm sure there's some small details I might be missing out on if I think of them I'll let you know. If anyone has any questions feel free to email me.
L8r
Will
First thing you're going to need to do is get a TH400 built. I went with a TH400 with reverse pattern valvebody and a transbrake. I also opted to swap out the stock 2.48 first gear ratio in the tranny for a slightly lower 2.75 first gear. The cost of swapping the first gear out was $480. I did this because the motor I'm planning on building for the car I will be running a big shot of nitrous and by going with a 2.75 first gear I could go with a little taller gear in the rear and not lose a whole lot in the 60'. I bought the tranny from a local shop here in Florida. The guy I bought it from builds trannies for 6 second dragsters so I figured that he would be able to build a tranny that would hold up to what I'm planning on throwing at it. The total cost of the tranny was 1450. I did look at getting the whole entire kit from yank. However two friends of mine purchased trannies from yank and had trouble with it. They had their trannies rebuilt by the guy who built mine and have had no trouble since. I personally think that the yank kit is a little bit over priced at over 3000 dollars. This is in no way a flame against yank I think yank makes a great converter and has great service. When I buy another converter for the new motor I will definately look at yanks.
With that being said the next thing you will need is a converter. Yanks kit includes one of their 9" thruster converters I believe. I went with a JW 10" converter. The same one GeorgeC is using and cutting 1.3x 60's with. The converter cost me around $460 with shipping. When you order a converter you may or may not need to get a crank pilot sleeve. When I went to install the tranny in the car for the first time the crank pilot on the converter was about 1/4" away from going into the crankshaft. I called JW and told them the problem and they sent me out a beautifully machined piece that slides right over the converter and extends the crank pilot to make it fit into the crank perfectly. They didn't charge me for this piece at all and everyone I talked to there was very helpful.
Next thing you will need to do is decide where to get a tranny crossmember from. Yank sells one that you can use your stock tq arm with for around $250. I talked to Brett at BMR and he made me one that I'm pretty sure he will be selling in the near future. The piece he sent me was awesome and fit great. It came powder coated black. I wont go into how much Brett charged me for this piece because I'm not sure how much he will be selling them for. I am almost positive that it will be a very good price and probably less than yanks. If you do go this route you will need to figure out something to do with your torque arm. The only options I know of that dont bolt up to the stock tranny are the spohn tq arm that mounts to where the tunnel brace mounts. Or the BMR trak-pak or extreme duty torque arm that mount on a crossmember welded in between their boxed SFC's. This is the tq arm I got.
Next you will need a shifter. There are alot of shifters that I have seen used and personally in my opinion none of them look as good as the hammer that I used. I think it looks the most factory and you dont have to hack up your console at all to make it fit. If you're swapping from an A4 to a TH400 you will need to get the upper console out of a 6speed car that has the leather shift boot. I was already swapping from a T-56 so I already had the console. To install the shifter I went to home depot and bought a piece of aluminum that was 2" x 24" x 1/4" I meausured the hole in the floorboard that the old shifter was in and cut two pieces from the aluminum to that length and mounted them in the center of the hole. I then placed the shifter on them to mark the holes the shifter would mount on. When I mounted the shifter I used some washers on the rear bolts to raise it up just a bit because when I installed the console it was hitting the shifter if I didn't use the spacers. I marked the hole for the shifter cable in the floorboard and then drilled it out. So after you get the shifter installed you will have two approximately 2" spaces on either side of the shifter so what I did was get some very thin 16ga aluminum and cut it out to shape and used the stock holes that mounted the old shifter and put them in. I then got some high temp silicone sealant and sealed all the gaps up from underneath the car. If you're swapping from a 6 speed car you will need to run the wires that were on your clutch switch over to the neutral safety switch on whatever shifter you buy so that the car will start only when the tranny is in park. I havent hooked up my backup lights yet but I'm sure it's not hard to figure out I just havent gotten around to it yet. Here are some pics of the shifter install
When you go to put the tranny up in the car it's best if you cut off the two ears that come off the side of the tranny for clearence of any headers you may put on the car. This pic shows where I cut
You will need to get a new driveshaft made. I bought my rear end and driveshaft from a friend who already had a th400 in his car so I didn't have to do this. I'm going to be purchasing a driveshaft from dennys soon however as my driveshaft is pretty out of balance right now.
When you bolt the tranny up to the block all the holes except one on the very top of the th400 will be used. this is 5 out of 6 bolts which should be plenty as long as they are torqued preperly.
For the tranny cooler iI bought a TCI cooler from jegs. It already has 6an line fittings right on the cooler. To do it this way you need the tranny cooler, 15 feet of -6an line, (2) 90deg -6an swivels, (2) 45deg -6an swivels, (2) -6an to 3/8 NPT fittings, and (2) -6an to -6an flare unions. The -6an to NPT fittings go into the tranny and the 45deg swivels go onto those. from there they go to the cooler which I mounted in front of my ac condenser on the passenger side of the car. On the tranny cooler you'll need the 90deg swivels and the -6an flare unions.
For the tranny dipstick I purchased one from lokar that was for a TH400 and was a firewall mount. This is a little bit hard to get to because it mounts WAYYYY on the back of the firewall on the car as it's only 2 feet long but it's not too bad.
After you get the tranny bolted in and shifter cable hooked up it's time to deal with the speed sensor. At the present time I havent hooked mine up yet so I dont know if thge way I did it will work or not. When I get around to doing it I'll post on how it turns out. But I can say that the way I did it is WAYYY cheaper than buying the sensor kit from yank for $250.
After all was said and done It took about 5 hours to get all the work done. and the car on the road. First impressions on the tranny are that it shifts HARD. Just putting the car into reverse or first shocks the tires and the whole car jerks. On the road it shifts great nice and crisp and exactly when I want it to. I love the hammer shifters ratchet action. It takes a little more getting used to than the 6speed as you have to remember what gear you're in and to remember to put it into first when you come to a stop. After driving this setup I wouldn't think about going back to the 6speed. My car is very lightly modded the way it sits now all I have done is a whisper lid/maf ends, and an exhaust cutout. before the TH400 with the 6speed I ran a best of 12.74 @ 110. With the th400 and 9" I was able to pull a 12.71 @ 107 the first time out with the car. That was on nittos and launching off the footbrake not the transbrake. I'd say the way the car sits a 12.5x is possible if i can cut a good 60'. The driveline is definately eating up some power I'm getting it dynoed again soon so I can see exactly how much.
Well that's it. Sorry for such a long post but since everyone was asking about this swap so often and with so many different posts I figured I'd try and put it all together in one. I'm sure there's some small details I might be missing out on if I think of them I'll let you know. If anyone has any questions feel free to email me.
L8r
Will
12-22-2001, 11:14 PM
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Re: Everything you ever wanted to know about a TH400 swap..I think Did you come up with a total price when it was all said and done? (I would like to know it because I am considering this swap, if you don't mind me asking) and how much do you think a shop would charge to do this conversion?
Thanks <img src="gr_grin.gif" border="0">
Thanks <img src="gr_grin.gif" border="0">
12-23-2001, 07:37 AM
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Re: Everything you ever wanted to know about a TH400 swap..I think Bigbos,
I'm on vacation right now (how's that for hardcore...writing a novel on vacation) When I get home I'll go through my receipts and get ya a total cost. If i had to guess right now. With just the stuff that's needed for the tranny was around 2800 dollars for everything including the shifter cooler driveshaft...everything you need.
John.
Be my guest man include it in the faq I have no problem with it at all. Always glad to include some helpful info
L8r
Will
I'm on vacation right now (how's that for hardcore...writing a novel on vacation) When I get home I'll go through my receipts and get ya a total cost. If i had to guess right now. With just the stuff that's needed for the tranny was around 2800 dollars for everything including the shifter cooler driveshaft...everything you need.
John.
Be my guest man include it in the faq I have no problem with it at all. Always glad to include some helpful info
L8r
Will
12-23-2001, 10:17 AM
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Re: Everything you ever wanted to know about a TH400 swap..I think Thanks because I am considering this instead of rebuilding my trans if I don't get warranty on it... <img src="gr_images/icons/cool.gif" border="0">
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12-23-2001, 07:08 PM
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Re: Everything you ever wanted to know about a TH400 swap..I think Sounds good, Will. You're going to like that JW converter! I have to correct you on one thing, though... I haven't cut any 1.3 60's yet. That's Colonel territory for now <img src="gr_stretch.gif" border="0">
12-23-2001, 10:27 PM
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Re: Everything you ever wanted to know about a TH400 swap..I think Well I stand corrected. I could have sworn you cut a 1.3x and posted about it one time. Guess I was mistaken. So far you're right though I do like the JW alot. It doesn't stall quite up to 4500 on my car most likely because I'm not making as much torque as you. It stalls up to about 4000 on the transbrake though but the car dies off the line. Guess it's time to build the motor up now that I have the driveline to hold the power.
L8r
Will <img src="graemlins/formula.gif" border="0" alt="[Pontiac]" />
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12-24-2001, 01:27 PM
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Re: Everything you ever wanted to know about a TH400 swap..I think Quick question. I understand you can get a TH350 that will bolt in and use the stock driveshaft. I know the TH350 is lighter, cheaper, and guys run 9s on them. Why did you select the TH400 over the TH350?
12-24-2001, 01:58 PM
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Re: Everything you ever wanted to know about a TH400 swap..I think Well after a long conversation with the guy that built my tranny. he basically told me that if my car was going to be strictly a track car than he would have suggested a th350 for it. But he said that while the TH350 can be built very strong he said that one of the parts in the th350 that is used to make it strong does not hold up very long at all if driven on the street alot. Since my car will be street driven heavily I decided to just put the TH400 in rather than rebuild the TH350 every 5-6000 miles. This kind of ended the debate for me which tranny can be built stronger. the TH350 can be built just as strong as the 400 but wont last very long being street driven. The th400 has the same strength but is better if you plan on doing alot of street driving.
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12-24-2001, 08:10 PM
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Re: Everything you ever wanted to know about a TH400 swap..I think [quote]Originally posted by BIGBOS:
<strong>How would I reprogram my 6-speed CPU?? Or can I?</strong><hr></blockquote>
BOS, im not 100% positive but im pretty sure you can have it reprogrammed. when i got my car back ed wright originally programmed it as a 6 speed and the car wouldn't shift so it had to be sent back.
<strong>How would I reprogram my 6-speed CPU?? Or can I?</strong><hr></blockquote>
BOS, im not 100% positive but im pretty sure you can have it reprogrammed. when i got my car back ed wright originally programmed it as a 6 speed and the car wouldn't shift so it had to be sent back.
12-24-2001, 09:02 PM
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Re: Everything you ever wanted to know about a TH400 swap..I think DOH!!! see i knew there would be things that I forgot to cover. Well as far as the PCM goes. If you're swapping from a T-56 there is no computer work to be done at all. You will get an SES light from the CAGS not being hooked up anymore but that can be taken care of with the skip shift eliminator I think. I havent done it yet. If you're swapping from an A4 you will need your computer done to delete the transmission control stuff. That's it as far as computer stuff goes. Hopefully there's nothing else I forgot to include. I'm going to try and put this all into a website when I get home from vacation and make it as clear, concise, and complete as I can.
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Will
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12-25-2001, 02:43 PM
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Re: Everything you ever wanted to know about a TH400 swap..I think ChassisEngineering makes a torque arm that doesn't bolt to the tranny. Only problem is that we have had to modify them a bit to get it work with cars where the headers have caused the I-Pipe to hang lower than stock.
12-25-2001, 03:46 PM
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Re: Everything you ever wanted to know about a TH400 swap..I think How often do you have to check the tranny fluid on the TH400 and how often do you want to get it checked for problems??
And what does the tranny usually run at temp wise <img src="gr_stretch.gif" border="0">
And what does the tranny usually run at temp wise <img src="gr_stretch.gif" border="0">
12-25-2001, 04:16 PM
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Re: Everything you ever wanted to know about a TH400 swap..I think I've been checking the fluid once a week. Doesn't seem to be losing any at all or getting any discoloration. I havent hooked up a temp gauge yet that's my next project to get one wired up and see where I'm at temp wise. I'm sure it's not overheating because the fluid is still a nice pink color. My tranny cooler is mounted in front of the AC condenser and I have my front bumper support and windshield washer fluid tank removed so I know it's getting plenty of air. Tranny took almost 11 quarts of fluid to fill up. I'm running a deep pan on it.
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Will
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02-01-2002, 11:34 PM
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Re: Everything you ever wanted to know about a TH400 swap..I think MacGyver did you use the GM sensor and reluctor to make the speedo work? if not what did you use? how does it work?
04-28-2002, 09:18 AM
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Re: Everything you ever wanted to know about a TH400 swap..I think MacGyver, did you ever get around to making a webpage for this install? I am fixing to do an A4 to TH350 or TH400 and would like to see this is more detail.
BTW, what is the piece you mentioned that does not hold up in the TH350 on the street vs the TH400?
Tim
BTW, what is the piece you mentioned that does not hold up in the TH350 on the street vs the TH400?
Tim