Author Topic: SM465 to TH400 conversion. Need info  (Read 6403 times)

Offline series60

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SM465 to TH400 conversion. Need info
« on: April 09, 2012, 08:45:24 am »
I have finally been able to get back to my ole' 1973 C-20. I have finished my sbc 406 rebuild and now have removed the SM-465 and will be replacing it with a TH-400. My questions are related to the installation of the TH-400 and the cross member I will need. I am assuming I will need a different cross-member because of the length of the tail shaft of the TH-400 compared to the SM-465. This TH-400 is out of a 1 ton motor home which has the universal on the output shaft. I was wondering if anyone has made this conversion and what I will need to look for. I will need a shifter also and would love input from anyone who has gone this route.

TIA,
Bill
Series60 AKA Mr. Bill
1973 C-20 / TH400
406+.30 CID

Offline wildcatjason

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SM465 to TH400 conversion. Need info
« Reply #1 on: April 09, 2012, 09:14:10 pm »
I have finally been able to get back to my ole' 1973 C-20. I have finished my sbc 406 rebuild and now have removed the SM-465 and will be replacing it with a TH-400. My questions are related to the installation of the TH-400 and the cross member I will need. I am assuming I will need a different cross-member because of the length of the tail shaft of the TH-400 compared to the SM-465. This TH-400 is out of a 1 ton motor home which has the universal on the output shaft. I was wondering if anyone has made this conversion and what I will need to look for. I will need a shifter also and would love input from anyone who has gone this route.

TIA,
Bill
Why don't you just move it?

Offline bake74

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Re: SM465 to TH400 conversion. Need info
« Reply #2 on: April 10, 2012, 06:09:05 am »
     Did you get the cross member with the trans ?  If so it should bolt into place.  You are going to need a donor vehicle for the shift linkage unless you got it with the trans, in that case some modifications are more than likely will need to be made for that one to work.
#1: The easiest and most obvious solution to any problem is 99% of the time correct.
#2: There is no such thing as impossible, it just takes longer.
  74 k10, 77k10    Tom

Offline series60

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Re: SM465 to TH400 conversion. Need info
« Reply #3 on: April 10, 2012, 06:26:54 am »
     Did you get the cross member with the trans ?  If so it should bolt into place.  You are going to need a donor vehicle for the shift linkage unless you got it with the trans, in that case some modifications are more than likely will need to be made for that one to work.

I have the donor vehicle which is based on a 1 ton and I wasn't sure yet if the cross-member from the 1 ton would fit. I will be removing the TH-400 and all associated parts this week end. Donor was column shift but I will be installing a floor shifter. Are there any cars models out there with floor shifters that might fit? Just trying to get a heads up on what to look for with this conversion.
Series60 AKA Mr. Bill
1973 C-20 / TH400
406+.30 CID

Offline bake74

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Re: SM465 to TH400 conversion. Need info
« Reply #4 on: April 11, 2012, 06:36:21 am »
     I am not sure if there is a car shifter out there that will bolt right in, depends on I guess what style hump you have in your truck.  The C series came with a couple of different styles.
     My suggestion is to take some careful measurements and spend some time in a wrecking yard or a pick-n-pull style yard and browse to see what would work.
#1: The easiest and most obvious solution to any problem is 99% of the time correct.
#2: There is no such thing as impossible, it just takes longer.
  74 k10, 77k10    Tom

Offline wildcatjason

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SM465 to TH400 conversion. Need info
« Reply #5 on: April 12, 2012, 09:49:01 pm »
     Did you get the cross member with the trans ?  If so it should bolt into place.  You are going to need a donor vehicle for the shift linkage unless you got it with the trans, in that case some modifications are more than likely will need to be made for that one to work.

I have the donor vehicle which is based on a 1 ton and I wasn't sure yet if the cross-member from the 1 ton would fit. I will be removing the TH-400 and all associated parts this week end. Donor was column shift but I will be installing a floor shifter. Are there any cars models out there with floor shifters that might fit? Just trying to get a heads up on what to look for with this conversion.
The aftermarket is flooded with floor shifters. Take a look at summit racing  I got 127 hits. heck I've thrown one in the trash in the past year out of an frito lay delivery truck I scrapped.

Offline zieg85

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Re: SM465 to TH400 conversion. Need info
« Reply #6 on: April 12, 2012, 10:04:21 pm »
I have seen them that would come close if not exact using the same hole that the SM465 used.  These applications are usually for street rods, sorry I can't remember the vendor but I think Mike Phillips was talking about one for his Blazer
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline jdl71

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Re: SM465 to TH400 conversion. Need info
« Reply #7 on: April 19, 2012, 08:41:36 pm »
I have seen them that would come close if not exact using the same hole that the SM465 used.  These applications are usually for street rods, sorry I can't remember the vendor but I think Mike Phillips was talking about one for his Blazer

Lokar perhaps?