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- - Tranny swap ?, I searched ... (https://67-72chevytrucks.com/vboard/showthread.php?t=309629)

cochino12

10-07-2008 09:22 PM

Tranny swap ?, I searched ...

Sorry for the dumb question, I searched but apparently I am search function slow ha ha.

I would like to swap the th350 for a 700r in my 86 lwb k20 w/np208 t-case. Other than the tranny itself what else is needed?

Thanks

old Rusty C10

10-07-2008 09:26 PM

Re: Tranny swap ?, I searched ...

for sure youll need the different indicator thing on the dash

cochino12

10-07-2008 09:28 PM

Re: Tranny swap ?, I searched ...

Quote:

Originally Posted by old Rusty C10 (Post 2920705)

for sure youll need the different indicator thing on the dash

ha ha, thats the only thing I was sure about.

Albatrossian

10-07-2008 09:33 PM

Re: Tranny swap ?, I searched ...

You might have to relocate the crossmember and/or get a different one since it's 4x4.. not sure though. The crossmember had to be moved when my truck was swapped from a 350 to a 700.

Jonboy

10-08-2008 08:08 AM

Re: Tranny swap ?, I searched ...

I am pretty sure it is a bolt in affair. Since your truck is an 86, all of the necessary holes should be in the frame if the crossmember does need to be moved. The Th350 thould have a TCC also, so that will plug in. The bracket for the kickdown cable is the same to hold the 700's TV cable. I don't remember the output shafts having different splines, but it has been over 10 years since I have had a 4WD. If you found a 700/208 combo for sale, it would bolt right in for sure.

abebummy26

10-08-2008 09:38 AM

Re: Tranny swap ?, I searched ...

Are you going to use your old Tcase?

JonnyTechMech

10-09-2008 11:34 AM

Re: Tranny swap ?, I searched ...

I haven't done such a swap, but don't you have to get a shorten drive shaft? It was my impression that the 700R4 was longer than a th350 or th400.

cochino12

10-09-2008 08:33 PM

Re: Tranny swap ?, I searched ...

Quote:

Originally Posted by abebummy26 (Post 2921333)

Are you going to use your old Tcase?

That was the plan

Quote:

Originally Posted by JonnyTechMech (Post 2923068)

I haven't done such a swap, but don't you have to get a shorten drive shaft? It was my impression that the 700R4 was longer than a th350 or th400.

Thats what I thought, I dont have a 700 here to measure though. I figured more people here would have done this swap?

Albatrossian

10-09-2008 08:37 PM

Re: Tranny swap ?, I searched ...

Between a TH350 with a 9-1/4" tail and a 700 there is only a 1/8 difference.

cochino12

10-09-2008 09:33 PM

Re: Tranny swap ?, I searched ...

Quote:

Originally Posted by Albatrossian (Post 2923663)

Between a TH350 with a 9-1/4" tail and a 700 there is only a 1/8 difference.

hmm so just a crossmember swap? sounds pretty simple guess I could get to the junk yard and do a little research too.

Thanks everyone

Jonboy

10-10-2008 09:16 AM

Re: Tranny swap ?, I searched ...

Quote:

Originally Posted by Albatrossian (Post 2923663)

Between a TH350 with a 9-1/4" tail and a 700 there is only a 1/8 difference.

The 4wd doesn't use the tailshaft housing. The flange that bolts to the extension housing bolts to the transfer case adapter, then the transfer case.

I was curious about the transfer case as I figured it might be easier to find a 700/208 combo pretty reasonable, and then you would know the splines would be the same.

abebummy26

10-10-2008 01:45 PM

Re: Tranny swap ?, I searched ...

The input shaft splines might be different on the Tcase. I'm not sure though.

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