SR4 to T4 swap? for Budget and Parts availability reasons (Canada) - JeepForum.com
 18Likes
Reply
 
LinkBack Thread Tools
post #1 of 17 Old 10-12-2021, 04:21 PM Thread Starter
Islander13
Registered User
 
Islander13's Avatar
1981 CJ7 
 
Join Date: Sep 2021
Location: Vancouver Island, Canada
Posts: 21
SR4 to T4 swap? for Budget and Parts availability reasons (Canada)

I did manage to get out for an hour long cruise yesterday after getting the '81 CJ7 running. I knew the SR4 was pretty sloppy when I started but found more quirks as I went along. Most notably trans would regularly not down shift into first at stops. The shifter would go into position, but not engage. Even trying 2nd, it would do the same thing. I found that if I went to reverse first - let it engage - then shift to first, it would work. It also seemed to work if I went to 3rd then back to first it sometimes worked. I ended up rolling through a few stop signs! After almost an hour of driving - there was a little whining out of the trans as well.

I am in Canada - on an Island off the west coast. Parts are virtually non existent. This is not a daily driver, or a mug buggy/rock crawler. Its a country road, sunny Sunday, forestry back road driver. I would like to keep it close to period correct, and budget is an issue. I'd like to keep the total trans rebuild/replace under 2k Canadian which is about 1500 US.

I have found a T4 trans (reportedly out of a late model CJ7) 300 miles away, that a CJ5 owner had bought but didn't fit in his 5. He says its supposed to be in decent shape for $350 USD. Its about another 150 to ship it to me. I have also searched the auto wreckers that specialize in jeeps and no one has any CJ parts. I talked to a trans shop locally with an old school mechanic who says that he could rebuild the SR4 and replace clutch and flywheel. I talked to another trans rebuilder who said they haven't seen a t4/5 for a long time (its Canada )

What I was thinking was to buy and ship the T4 for $500 - take it to the trans shop and check/rebuild if necessary for another $500-1000 and swap out the SR4 for the T4.

I know already that a lot of people will say that the T4 is a weak trans that isn't an upgrade. But I do have limited options. What I am thinking is taking the $500 gamble on the T4.
From all that I've read - the T4/5 is a plug and play swap for the SR4.

Pics of the T4 for sale are attached. I'm not sure if any of the casing stamps can confirm whether its a CJ7 T4.

Any advice is appreciated! Even T4 haters...

Attached Thumbnails
Screen Shot 2021-10-12 at 3.16.58 PM.jpg   Screen Shot 2021-10-12 at 3.16.38 PM.jpg   Screen Shot 2021-10-12 at 3.16.20 PM.jpg   Screen Shot 2021-10-12 at 3.15.57 PM.jpg   Screen Shot 2021-10-12 at 3.15.38 PM.jpg  

Screen Shot 2021-10-12 at 3.15.07 PM.jpg  

Ken D
1981 CJ7
258 4spd
Islander13 is offline  
Sponsored Links
Advertisement
 
post #2 of 17 Old 10-12-2021, 08:16 PM
Rtracy2001
Registered User
1985 CJ7 
 
Join Date: Oct 2013
Location: Blackfoot
Posts: 431
I have no first hand experience with the SR4 transmission, but I have run T4s and T5s prior to my SM420 conversion. Novak has some info on the SR4 and T4/T5 (The T5 would also be an easy swap and would add overdrive):

https://www.novak-adapt.com/knowledg.../manual/t4-t5/
https://www.novak-adapt.com/knowledg...ns/manual/sr4/

If you can find an SM420 or SM465, either one would be a significant upgrade over the SR4 and conversion parts are probably within your price range ~$600 US). Since the SM465 was used in a huge number of GM trucks, they should be far more available than a T4.T5. If you can't find one, Novak does offer a fully rebuilt and adapted SM465 for about $2K US. (I picked up my SM420 for $100 US.)

https://www.novak-adapt.com/knowledg.../manual/sm465/
https://www.novak-adapt.com/knowledg.../manual/sm420/

As you said your Jeep is a sunny day dirt road rig, and we are heading into winter, spending some time looking for either a cheaper (closer) T5 or looking into an SM420/465 might pay big dividends in the long run and you may be able to get it back on the road around springtime.
Islander13 likes this.

Every 20 minute job is just one broken bolt away from a three day ordeal.
Rtracy2001 is offline  
post #3 of 17 Old 10-13-2021, 06:13 AM
hodge5
Registered User
 
hodge5's Avatar
1985 CJ7 
 
Join Date: Oct 2019
Posts: 87
If it were me, and I had limited funds and resources, I'd chose the T4 over the SR4. I think that it's marginally better, and you shouldn't get into the expenses incurred in swapping to a 465 or other non-standard transmission. You said that your funds are limited and that you want to keep it original, so the T4 (0r a T5, if you come across one) is a viable option.
I have a T5 in mine, and I'm very happy with it. It's got a decent 1st gear, and mine is tight and without issue. My uses are similar to yours.
Islander13 likes this.
hodge5 is offline  
 
post #4 of 17 Old 10-13-2021, 09:28 PM
only in a jeep cj
Registered User
1986 CJ7 
 
Join Date: Jun 2001
Location: Mobile
Posts: 6,151
I have had all 3. The SR 4 is totally crap. Reverse is in a bad spot, and awkward to get into.
The T4 is way better but still no overdrive. So you’d be spending a grand plus just to get rid of a weird shifting unit. Hold out for a T 5 and gain the overdrive but only if your axle gearing matches the tire height. If your geared too high, 5th will be too hard to use. I have T5s and really like them. They shift fine and allow much higher speeds. I think I’m at 2700 rpm at 75 mph.
I have swapped SR4 and T5s snd can confirm that only the transmission (and its shifter) are needed. Plug and play.
keith460 and Islander13 like this.

Ed
1975 CJ-6 1983 CJ-8
1986 CJ-7 Laredo 1986 2003 Inca Gold TJ Rubicon
2012 JKUR RHD
only in a jeep cj is offline  
post #5 of 17 Old 10-14-2021, 06:50 AM
Matt1981CJ7
Registered User
 
Matt1981CJ7's Avatar
1981 CJ7 
 
Join Date: May 2011
Location: Elbert
Posts: 23,171
I'm guessing the OP's '81 has 2.73 gears like mine does. If so, an overdrive would be pretty useless.

Matt


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Matt1981CJ7 is offline  
post #6 of 17 Old 10-14-2021, 09:40 AM Thread Starter
Islander13
Registered User
 
Islander13's Avatar
1981 CJ7 
 
Join Date: Sep 2021
Location: Vancouver Island, Canada
Posts: 21
Quote:
Originally Posted by Matt1981CJ7 View Post
I'm guessing the OP's '81 has 2.73 gears like mine does. If so, an overdrive would be pretty useless.

Matt
I'm guessing Matt's right. I don't know how to confirm the gearing, but when I was driving it for an hour - though I didn't go on the highway - I barely used 4th.

I've made a deal for the T4 and I'm getting it shipped down to me next week (hopefully). It's a bit of a gamble but before I do anything with the T4, I'm taking the jeep to an old school mechanic who I really trust. He'll get it up on a hoist and do a deeper dive into what else I might need to spend money on.

It is a very solid frame, and the body is surprisingly much better than I had expected. When I saw all the checker plate, when I first went to look at the CJ, I assumed that it was all he aluminum holding it together. But there are only a couple of rust through holes in the pan that I can treat for now. I may fix them later. When my son is finished college next year, its something that I'd like to share in with him.

Not to get too sappy, but I was diagnosed with a type of blood cancer last year and went through a stem cell transplant. That was actually the reason I bought this CJ. I feel great these days, and I'm in full remission now, but I do realize just how valuable time is. And I'd rather be driving than wrenching. When I say a sunny day driver - it doesn't have to be a warm sunny day. Hell... it doesn't even have to be sunny - just not raining.

Thanks for the feedback. The internet can be a great thing!

Ken

Ken D
1981 CJ7
258 4spd
Islander13 is offline  
post #7 of 17 Old 10-14-2021, 09:09 PM
howardellis
Registered User
 
Join Date: Oct 2021
Posts: 5
The T4 is far superior, but there is still no overdrive. So you'd have to pay a $1,000 or more to get rid of a strange moving unit. If you wait for a T 5, you'll get overdrive, but only if your axle gearing matches your tire height. 5th will be difficult to use if your gearing is too high. I have T5s and enjoy them a lot. They shift smoothly and enable for significantly faster speeds. At 75 mph, I believe I'm at 2700 rpm.
howardellis is offline  
post #8 of 17 Old 10-15-2021, 11:10 AM
devildog80
Registered User
 
devildog80's Avatar
1981 CJ5 
 
Join Date: Jun 2019
Location: Apache Junction
Posts: 458
OP lives on an island, barely uses 4th gear on an hour long drive with existing 4 speed, so don't see that 5th gear would ever be used. But....with 5 gears, the rpm spread between the lower 1-4 should be an advantage.
Glad to hear you are a Cancer survivor, do live every minute you are given, and not much better way to do that than with an old Jeep
devildog80 is offline  
post #9 of 17 Old 10-15-2021, 01:47 PM
bob4703
Registered User
1974 CJ5 
 
Join Date: Feb 2015
Location: Easley
Posts: 3,054
Happy that you are feeling better. Staying active whether it be working on your Jeep or driving it is the best therapy you can do. I have a friend in our Jeep club who is 35 years young and was recently diagnosed with cancer in both her breasts. She has completed one type of chemo and is undergoing a second type. She will then go through radiation on one breast and then surgery on it. Then she will undergo radiation on the second and then surgery on it. After that she will have reconstructive surgery one at a time. She she has been undergoing treatment since July and if all goes well and on schedule she will finish by Christmas next year. She is so proud that she hasn't missed a day of work yet. She has left early for treatment and a couple of times because she didn't feel well, but she has been there every day. Her husband is a USMC veteran and is deputy sheriff is proud to say he isn't the tough one in the family she is. When I saw her last Saturday evening she showed up by herself along with her seven year old and almost two year old sons. Hubby was late getting off shift and she got tired of waiting for him. Remember Candace in your prayers. I'll add you to mine.
Islander13 likes this.

-----

Paved roads are prime examples of government over spending!
bob4703 is offline  
post #10 of 17 Old 10-15-2021, 02:56 PM
hodge5
Registered User
 
hodge5's Avatar
1985 CJ7 
 
Join Date: Oct 2019
Posts: 87
"When my son is finished college next year, its something that I'd like to share in with him."

We lost our 17 year old son, in 2010. He and I were tight. The last project together was putting a transmission in his Honda. I miss, painfully, those times together.
Enjoy your time with your son, make the most of it. You know how precious each day is, and the next not guaranteed.
bob4703 and Islander13 like this.
hodge5 is offline  
post #11 of 17 Old 10-15-2021, 04:47 PM
fibersport
Registered User
 
Join Date: Feb 2021
Location: Valparaiso
Posts: 96
I've really got nothing to add other than congratulations on being a survivor. I also wanted to remember Candace too. My wife is just finishing up something very similar and I know how tough it can be both physically and mentally. Amazing how strong people can be, thoughts and prayers to you both -

I have a T4 in my '84. Not sure what gearing it has but I was thinking of swapping a T5 into it, I have a T176 that needs to be rebuilt. After reading the comments about a 5 speed and high ratio gears, I may just rebuild the T176 and leave it!
bob4703 and Islander13 like this.

1984 CJ7 Renegade
4.2 with 4 speed
researching other details!
fibersport is offline  
post #12 of 17 Old 10-15-2021, 05:23 PM
claudvandebek
Registered User
 
Join Date: Sep 2021
Posts: 7
claudvandebek

Quote:
Originally Posted by Islander13 View Post
I did manage to get out for an hour long cruise yesterday after getting the '81 CJ7 running. I knew the SR4 was pretty sloppy when I started but found more quirks as I went along. Most notably trans would regularly not down shift into first at stops. The shifter would go into position, but not engage. Even trying 2nd, it would do the same thing. I found that if I went to reverse first - let it engage - then shift to first, it would work. It snaptube vidmate also seemed to work if I went to 3rd then back to first it sometimes worked. I ended up rolling through a few stop signs! After almost an hour of driving - there was a little whining out of the trans as well.

I am in Canada - on an Island off the west coast. Parts are virtually non existent. This is not a daily driver, or a mug buggy/rock crawler. Its a country road, sunny Sunday, forestry back road driver. I would like to keep it close to period correct, and budget is an issue. I'd like to keep the total trans rebuild/replace under 2k Canadian which is about 1500 US.

I have found a T4 trans (reportedly out of a late model CJ7) 300 miles away, that a CJ5 owner had bought but didn't fit in his 5. He says its supposed to be in decent shape for $350 USD. Its about another 150 to ship it to me. I have also searched the auto wreckers that specialize in jeeps and no one has any CJ parts. I talked to a trans shop locally with an old school mechanic who says that he could rebuild the SR4 and replace clutch and flywheel. I talked to another trans rebuilder who said they haven't seen a t4/5 for a long time (its Canada )

What I was thinking was to buy and ship the T4 for $500 - take it to the trans shop and check/rebuild if necessary for another $500-1000 and swap out the SR4 for the T4.

I know already that a lot of people will say that the T4 is a weak trans that isn't an upgrade. But I do have limited options. What I am thinking is taking the $500 gamble on the T4.
From all that I've read - the T4/5 is a plug and play swap for the SR4.

Pics of the T4 for sale are attached. I'm not sure if any of the casing stamps can confirm whether its a CJ7 T4.

Any advice is appreciated! Even T4 haters...
personnally I would go with t4
Islander13 likes this.

Last edited by claudvandebek; 10-16-2021 at 05:54 AM.
claudvandebek is offline  
post #13 of 17 Old 10-17-2021, 08:09 PM
howardellis
Registered User
 
Join Date: Oct 2021
Posts: 5
Quote:
Originally Posted by fibersport View Post
I've really got nothing to add other than congratulations on being a survivor. I also wanted to remember Candace too. My wife is just finishing up something very similar and I know how tough it can be both physically and mentally. Amazing how strong people can be, thoughts and prayers to you both -

I have a T4 in my '84. Not sure what gearing it has but I was thinking of swapping a T5 into it, I have a T176 that needs to be rebuilt. After reading the comments about 5 speed and high ratio gears, I may just rebuild the T176 and leave it!
I have the same opinion as you, I have also read a lot about whether to change the speed of the car 5 wheels? If you have good results when replacing them, please share them here. Thanks!


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
howardellis is offline  
post #14 of 17 Old 10-18-2021, 11:41 AM Thread Starter
Islander13
Registered User
 
Islander13's Avatar
1981 CJ7 
 
Join Date: Sep 2021
Location: Vancouver Island, Canada
Posts: 21
Thanks for the advice and a heartfelt thanks for the encouragement. Hodge5 I can't imagine how painful your loss is... And bob - I'll definitely add Candace to my prayers as well as fibersports wife.
The reason that I mentioned being a survivor was that I have found that I value time, and how I spend it, so much more now. I want to get this CJ up and running sooner rather than later. We have pretty mild winters here, so any sunny day will do. Hell - any non-rainy day will do. I heard someone say that driving a CJ is the closest thing on 4 wheels to riding a horse... Probably not that far off. Even just my one hour drive on a sunny Sunday with the top and doors off was such a blast. I couldn't get the smile off my face.
bob4703 and fibersport like this.

Ken D
1981 CJ7
258 4spd
Islander13 is offline  
post #15 of 17 Old 10-18-2021, 06:16 PM
devildog80
Registered User
 
devildog80's Avatar
1981 CJ5 
 
Join Date: Jun 2019
Location: Apache Junction
Posts: 458
Take that drive every day you can, and keep smiling
Islander13 likes this.

'81 CJ5, 258 I6, T176 4 spd, 300 TC, D30 Front NT, 3.31, 2-Piece AMC 20 rear NT, 3.31
devildog80 is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome