Considering manual to auto swap.

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

TCK1

Junior Member
Joined
Oct 12, 2022
Posts
8
Reaction score
7
Location
Idaho
First Name
Travis
Truck Year
81
Truck Model
k25
Engine Size
5.7
Hello all,

I’m considering a swap from a Sm465 to an auto. I recently had my Sm465 rebuilt in my 81 k25, while the mechanic was in there I had him replace the clutch as well. 6 months later this pickup is going in for the 5th time because the clutch keeps having problems. It has been replaced once since the original work was done covered by his warranty. I never had a problem with the clutch before it was taken in the first time. Right now every so often the clutch pedal starts vibrating and the clutch starts whining when depressed. This was the reason why it went in for the warranty work. Now it’s doing it again. Getting progressively worse as I go. I’m about at my wits end with this continuing problem. Any ideas on what is going on would be greatly appreciated. This is why I’m considering a swap to an auto. With that being said which auto transmission would be the easiest to swap to. Considering I’ll probably have to switch the transfer case, and drive lines as well. But the least amount of modifications would be preferable.
 

bucket

Super Moderator
Staff member
Super Moderator
Joined
Aug 3, 2010
Posts
28,956
Reaction score
23,465
Location
Usually not in Ohio
First Name
Andy
Truck Year
'77, '78, '79, '84, '88
Truck Model
K5 thru K30
Engine Size
350-454
Do you know specifically what brand and grade of parts were used? I've seen various clutch issues that were caused from cheap, low quality parts.
 

bucket

Super Moderator
Staff member
Super Moderator
Joined
Aug 3, 2010
Posts
28,956
Reaction score
23,465
Location
Usually not in Ohio
First Name
Andy
Truck Year
'77, '78, '79, '84, '88
Truck Model
K5 thru K30
Engine Size
350-454
Also, assuming you have the original 465/208 combo, a TH400 with "tall style" 208 adapter will be a bolt-in swap. You can also use the '85+ style "short" adapter but you will have to use an '85+ style trans crossmember as well. Your stock drive shafts will be the correct length.
 

Turbo4whl

Supporting Member
Supporting Member
Joined
Oct 30, 2019
Posts
2,837
Reaction score
6,352
Location
Downingtown, PA
First Name
Wayne
Truck Year
1974
Truck Model
Jimmy
Engine Size
350
Do you know specifically what brand and grade of parts were used? I've seen various clutch issues that were caused from cheap, low quality parts.
Andy has this right. The problem is getting and identifying the good parts. The first clutch I put in my '74 were parts house, rebuilt pressure plate, new disc and bearing. The 3 finger type pressure plate had one finger crack right away, new clutch would not release. Bought all new parts from the dealer for twice the price and had no problems. This was years ago, I doubt the current dealers have any parts for our trucks other than an oil filter.
 

Latest posts

Forum statistics

Threads
41,847
Posts
903,379
Members
33,361
Latest member
iiixtremeiii
Top