Okay this is going to be kind of a long post and I apologize for the length of this post. I’ve done the searches and can’t find an answer to this question. However, I really need some advice and input from anyone running an AT in a CJ-5 or anything else for that matter that will provide me with any insight into this swap. After 23 years of having a manual (T-150. T-18, SM-420) in this Jeep its time to switch to an auto. I know basically nothing about autos and what little I know is about THs.
I’ve got a 383 SBC in my 79 CJ-5 w/ SM-420/Dana 300 4:1/RC Dana 60. Clearly I don’t have a lot of drive shaft length and would not like for it not to be any shorter than it has to be. I use the Novak adapter from the SM-420 to the D300 (it’s an inch shorter than AA) and I have the short D300 (3.5 inch output). The engine has approximately 430 ft-lb peak torque and a pretty flat torque curve with probably around 300 ft-lb at 2,000 rpm. The current tranny setup measures 30.75 inches from the back of the block to the center face of the output yoke. I have SOA about (5 to 5.5inches of lift), with rear springs shackled front and rear w/four link and no wheelbase stretch. I have pretty good travel therefore a short drive shaft is a critical issue. I can ramp 1000 with open diffs (never tried to ramp it with both ARB’s locked as the airlines weren’t connected at the time).
I want to swap in an automatic tranny. I know the common swap is TH350. The approach that really is interesting to me is to use a Torque Flite 904 that was behind the GM 151 4 cyl. Iron Duke in the the 1980-1983 CJ-7s is especially interesting to me for two reasons:
1. It bolts directly to a SBC and Dana 300 without any adapters.
2. It’s short at 16 inches (but don’t know the tailshaft housing length)
At the 2001 ARCA Finals at Farmington, a brown CJ-5 that was competing had an AMC 360 with TF 904 and an Atlas II. The owner told me he had moved the rear axle back 2 inches and of course it had to run a fuel cell in its bed. Unfortunately, I didn’t get a chance to measure the overall length of the tranny and transfer case. According to the video of the 1999 Johnson Valley rock crawling event, Mike Vokoun’s (I believe he was Joel Randall’s spotter) 1980 CJ-5 is running a TF 904 behind a SBC TPI. I think also that Joel Randall at one time had a 904 in his old CJ-5 but I’m not sure. I don’t know how to get in touch with either of these guys to ask them about their setups. One of the guys in my Jeep club ran a TF 904 behind and warmed-up 350 and after it breaking twice he went to a TH-400 in his CJ-5. But as I recall he didn’t really build the TF 904 either.
I have been told by Turbo Action in Florida, a shop that supposedly did TF’s for Chrysler backed factory drag racers, that they have built TF 904’s that can live behind a hemi. I have been told by others that even built TF 904’s can’t handle the stress of rock crawling. Turbo Action suggested their forward pattern manual valve body which has compression braking in first gear, 5 pack built clutch pack from TF 999, Kevlar bands, built converter, deep pan, and TF 999 2.74 first gear. Turbo Action thinks they could build a TF 904 that can live for me. We talked about the high temperatures in the desert and lack of flowing air encountered during rock crawling and interestingly they thought I should use an air conditioning condenser for my AT cooler. They said if the transmission pukes I can easily wash out the large diameter tubing out whereas the other types you can never really get clean. Is anybody running an AC condenser with there AT? It kinds of concerns me that they even mentioned the AT puking - I don’t know how to take the comment.
According to Advance Adapters the TF 727, 904, 909, and 999 have a case length of 16” which is the shortest of any automatic I know of that is a possible for a CJ-5. On a previous PBB thread I got the length of a TF 999 as 22.5 inches for a 2000 TJ and I assume that includes the tailshaft housing. However, I still don’t know if this tailshaft length has been constant throughout the years for 727s, 904s, and 999s and the numerous transfer cases behind them..
My questions are:
1. Since the TF904 w/Dana 300 was in 80-83 Jeeps with the 4 banger Iron Duke I think I can use the factory tail-shaft housing between the transmission and Dana 300. Is this true? What is the length of this tail shaft housing?
2. How can I identify the transmission by any numbers stamped on the case?
3. What do I use for a flex plate and torque converter for the TF904 to 86-up SBC swap.
4. I assume there is no front driveshaft interference since the TF904/Dana 300 was a factory combination. Is this a good assumption?
5. What can I do about the kick down linkage? I am running an LT-4. A while back an acquaintance of mine built a kick-down linkage for a TF999 behind a TPI SBC in a CJ-7 for one of his customers. He said it was a nightmare to fabricate and charged $800 for it. Should I just use a manual valve body and just forget the kick-down linkage?
6. Turbo Action thinks somebody makes a gear lower for the TF 904 that is lower than the 2.74 for the TF 999. Does anyone have a source for a lower gear?
7. Is there a TF 999 that will bolt directly to a 86-up SBC without an adapter? I think the answer is no, but just had to ask.
Thanks!
I’ve got a 383 SBC in my 79 CJ-5 w/ SM-420/Dana 300 4:1/RC Dana 60. Clearly I don’t have a lot of drive shaft length and would not like for it not to be any shorter than it has to be. I use the Novak adapter from the SM-420 to the D300 (it’s an inch shorter than AA) and I have the short D300 (3.5 inch output). The engine has approximately 430 ft-lb peak torque and a pretty flat torque curve with probably around 300 ft-lb at 2,000 rpm. The current tranny setup measures 30.75 inches from the back of the block to the center face of the output yoke. I have SOA about (5 to 5.5inches of lift), with rear springs shackled front and rear w/four link and no wheelbase stretch. I have pretty good travel therefore a short drive shaft is a critical issue. I can ramp 1000 with open diffs (never tried to ramp it with both ARB’s locked as the airlines weren’t connected at the time).
I want to swap in an automatic tranny. I know the common swap is TH350. The approach that really is interesting to me is to use a Torque Flite 904 that was behind the GM 151 4 cyl. Iron Duke in the the 1980-1983 CJ-7s is especially interesting to me for two reasons:
1. It bolts directly to a SBC and Dana 300 without any adapters.
2. It’s short at 16 inches (but don’t know the tailshaft housing length)
At the 2001 ARCA Finals at Farmington, a brown CJ-5 that was competing had an AMC 360 with TF 904 and an Atlas II. The owner told me he had moved the rear axle back 2 inches and of course it had to run a fuel cell in its bed. Unfortunately, I didn’t get a chance to measure the overall length of the tranny and transfer case. According to the video of the 1999 Johnson Valley rock crawling event, Mike Vokoun’s (I believe he was Joel Randall’s spotter) 1980 CJ-5 is running a TF 904 behind a SBC TPI. I think also that Joel Randall at one time had a 904 in his old CJ-5 but I’m not sure. I don’t know how to get in touch with either of these guys to ask them about their setups. One of the guys in my Jeep club ran a TF 904 behind and warmed-up 350 and after it breaking twice he went to a TH-400 in his CJ-5. But as I recall he didn’t really build the TF 904 either.
I have been told by Turbo Action in Florida, a shop that supposedly did TF’s for Chrysler backed factory drag racers, that they have built TF 904’s that can live behind a hemi. I have been told by others that even built TF 904’s can’t handle the stress of rock crawling. Turbo Action suggested their forward pattern manual valve body which has compression braking in first gear, 5 pack built clutch pack from TF 999, Kevlar bands, built converter, deep pan, and TF 999 2.74 first gear. Turbo Action thinks they could build a TF 904 that can live for me. We talked about the high temperatures in the desert and lack of flowing air encountered during rock crawling and interestingly they thought I should use an air conditioning condenser for my AT cooler. They said if the transmission pukes I can easily wash out the large diameter tubing out whereas the other types you can never really get clean. Is anybody running an AC condenser with there AT? It kinds of concerns me that they even mentioned the AT puking - I don’t know how to take the comment.
According to Advance Adapters the TF 727, 904, 909, and 999 have a case length of 16” which is the shortest of any automatic I know of that is a possible for a CJ-5. On a previous PBB thread I got the length of a TF 999 as 22.5 inches for a 2000 TJ and I assume that includes the tailshaft housing. However, I still don’t know if this tailshaft length has been constant throughout the years for 727s, 904s, and 999s and the numerous transfer cases behind them..
My questions are:
1. Since the TF904 w/Dana 300 was in 80-83 Jeeps with the 4 banger Iron Duke I think I can use the factory tail-shaft housing between the transmission and Dana 300. Is this true? What is the length of this tail shaft housing?
2. How can I identify the transmission by any numbers stamped on the case?
3. What do I use for a flex plate and torque converter for the TF904 to 86-up SBC swap.
4. I assume there is no front driveshaft interference since the TF904/Dana 300 was a factory combination. Is this a good assumption?
5. What can I do about the kick down linkage? I am running an LT-4. A while back an acquaintance of mine built a kick-down linkage for a TF999 behind a TPI SBC in a CJ-7 for one of his customers. He said it was a nightmare to fabricate and charged $800 for it. Should I just use a manual valve body and just forget the kick-down linkage?
6. Turbo Action thinks somebody makes a gear lower for the TF 904 that is lower than the 2.74 for the TF 999. Does anyone have a source for a lower gear?
7. Is there a TF 999 that will bolt directly to a 86-up SBC without an adapter? I think the answer is no, but just had to ask.
Thanks!