chevy motor/axle swap into a yj

BiggDaddy · 01-19-2008, 08:42 PM

Hello all, I've got a buddy that is putting a chevy 350 into a yj with some chevy axles.

What we do know
He's got a '90 yj islander that is puke green/teal colored. He's got the motor, tranny, and xcase mounted in the jeep now. Looks like a dana 44 chevy front axle, and a rear 12 bolt. The 12 bolt has 3.07 gears, but haven't opened up the front yet.

What we don't know for sure
1. Wondering if we can hack into the yj wiring harness to hook the engine up to the dash etc.., but facing the reality that we will probably have to get a painless kit and use that.

2. Probably going to need some custom driveshafts, but were wondering if anybody knows of any that may work, front or rear.

3. Whether or not we need to shorten the front axle. The rear axle will stay the same length. The front axle though, will need to be shortened by about 1.5-2 inches to center it on the frame and use the cast spring mount in the differential.

4. Whether we can use the same steering setup that is available. Yj box, with either yj tie rod or use the chevy tie rod (probably depends on whether or not we shorten the axle.

This is about it for now, but realize there is still a lot of work to do. Plans are probably to be finished either this fall or next spring, not real sure. Just depends on what needs to be done, and what kind of time and money he has to put into it. thanks for all of your help.

BiggDaddy

94Dodge Truggy · 01-19-2008, 11:01 PM

You can hack into the stock harness but it will be a very long and tedious task where as the painless wiring will save u time. On the axle just relocate the perches and run a custom offset rims. Plan on having to resize the driveshafts. The painless wiring harness will be money well spent and the dash will be more functional. Good luck!

sarge · 01-20-2008, 12:01 AM

post up on miami valley 4 wheelers site . www.mv4w.com

I think it's "teach " on their site that can splice your harness up in an afternoon so it all works just like it did stock .

Mike F · 01-20-2008, 01:09 PM

Quote:

Originally Posted by sarge

post up on miami valley 4 wheelers site . www.mv4w.com

I think it's "teach " on their site that can splice your harness up in an afternoon so it all works just like it did stock .

I don't think Teach can do that but he might.

I have spliced the YJ harness a few times to fit different motors. I spliced the one in Shawn B's YJ that Sarge is thinking about.

What year of chevy motor do you have and do you have the chevy motor harness.

itbrokeagain · 01-20-2008, 02:44 PM

Quote:

Originally Posted by BiggDaddy

3. Whether or not we need to shorten the front axle. The rear axle will stay the same length. The front axle though, will need to be shortened by about 1.5-2 inches to center it on the frame and use the cast spring mount in the differential.

BiggDaddy

If you shorten the front and dont do the rear it will look funny. Usually when truck axles are installed you need to move the front springs to the outside of the frame. Im sure someone here had a pic to post up if you dont know what Im talking about.

sarge · 01-21-2008, 02:20 AM

Quote:

Originally Posted by Mike F

I don't think Teach can do that but he might.

I have spliced the YJ harness a few times to fit different motors. I spliced the one in Shawn B's YJ that Sarge is thinking about.

What year of chevy motor do you have and do you have the chevy motor harness.

Sorry Mike , I couldn't remember who did Shawns off hand !

carwash · 01-21-2008, 09:55 AM

Quote:

Originally Posted by itbrokeagain

If you shorten the front and dont do the rear it will look funny. Usually when truck axles are installed you need to move the front springs to the outside of the frame. Im sure someone here had a pic to post up if you dont know what Im talking about.

yes, don't shorten the axle, outboard the frame spring mount areas...

blazerbrad · 01-21-2008, 10:49 AM

As already mentioned, it would be much simpler to move the front spring mounts then actually shortening the axle, especially for just a couple of inches. I believe there are companies out there that even make kits for this.

BiggDaddy · 01-21-2008, 08:11 PM

Hey thanks everybody. We'll take this advice and get on with the project. I'll try and snap a few pics next time I'm over so you can see how ugly this thing is. I'm sure I'll have some more questions for you sooner or later too. Thanks again.

BiggDaddy

BiggDaddy · 01-31-2008, 03:54 AM

Here are some pics. Took forever to figure out software to resize them.

muddinredneck513 · 01-31-2008, 04:02 AM

he get that jeep off craiglist? i seen one on there a while back just like it with the sun lookin thing on the door!! if not it was its twin!!!

JeepHD · 01-31-2008, 10:26 AM

Quote:

Originally Posted by muddinredneck513

he get that jeep off craiglist? i seen one on there a while back just like it with the sun lookin thing on the door!! if not it was its twin!!!

He picked it up at a swap meet about 2 years ago. Sat in my barn until recently and hasn't been listed on craiglist.

JeepHD · 01-31-2008, 10:33 AM

Quote:

Originally Posted by BiggDaddy

Here are some pics. Took forever to figure out software to resize them.

Front doesn't really look like a 44. Can anyone verify if it is or isn't. Maybe a GM 10 bolt. Are these axles worth using?

BiggDaddy · 01-31-2008, 10:38 AM

Nope. It's a package deal they had for a couple of years. I think '90 and'91. Picked up the whole Jeep for $500 and a couple of cj axles.

94Dodge Truggy · 01-31-2008, 10:56 AM

Appears to be light duty axles. What size and brand tire do you plan on running?

JeepHD · 01-31-2008, 11:03 AM

Quote:

Originally Posted by 94Dodge Truggy

Appears to be light duty axles. What size and brand tire do you plan on running?

Not sure but I would guess 33s or 35s. Probably whatever we find for him cheap. I am going to suggest to him that we look for some different axles, especially running them behind a mild built 350.

JET455 · 01-31-2008, 11:38 AM

Axles are 10 bolts the front will take 35's I would not go larger then 33's though casue the rear is a c-clip axle.

94Dodge Truggy · 01-31-2008, 11:47 AM

Buy my 60/70 combo and be done! I also have a 30 front and 35 rear with 4.10 ratio from a 94 wrangler. Make me an offer!

carwash · 01-31-2008, 11:57 AM

truggy is having one hell of an axle sale right now, that's for sure.

blazerbrad · 01-31-2008, 04:02 PM

Looks like a 10-bolt front axle to me. But whether it's a D44 or 10-bolt shouldn't make any difference because they are basically identical in strength.

In my opinion that fact that the rear axle is a c-clip design is a moot point in regards to strength. The c-clip in no way makes the axle any weaker than if everything else was identical with the exception of the c-clips. Sure, if you break a shaft it can spit off the tire end, but so can a flanged (non c-clip) axle (I've seen two flanged D44 rear axles do this).

But in any case they aren't exactly the epitome of beef in regards to axles, and the gearing sucks, but should hold up reasonably well under a light vehicle only running 33-35" tires. This also assuming they are in good condition, if the shafts and such have already been beat on hard for 20+ years then they would have a lot of fatigue life.

sarge · 02-01-2008, 12:06 PM

my old rig ( now Hybrids ) was on 10 bolts and I beat the crap out of it , never had a problem with the rear and it was welded. Started breaking fronts only after welding it up , I was running 35" boggers and a mild 350.
Biggest mistake I made was going to a 14 bolt in the rear and still running 35's , it was worse then running 31's with the 10 bolts . " no clearance!!"
I would run the 10 bolts and up to 35's for now. Get a couple trail spares and have fun. The 10 bolts are dirt cheap and easy to work on and easy to find in the scrap yards.

JeepHD · 02-01-2008, 12:44 PM

Quote:

Originally Posted by sarge

my old rig ( now Hybrids ) was on 10 bolts and I beat the crap out of it , never had a problem with the rear and it was welded. Started breaking fronts only after welding it up , I was running 35" boggers and a mild 350.
Biggest mistake I made was going to a 14 bolt in the rear and still running 35's , it was worse then running 31's with the 10 bolts . " no clearance!!"
I would run the 10 bolts and up to 35's for now. Get a couple trail spares and have fun. The 10 bolts are dirt cheap and easy to work on and easy to find in the scrap yards.

Great thanks. I'll suggest he stick with the 10bolts for now then. I know they worked on it last night, but I was miserable with a cold so I didn't make it.

01-19-2008, 08:42 PM	#1
BiggDaddy Join Date: Nov 2007 Location: Sidney, Ohio Posts: 52	chevy motor/axle swap into a yj Hello all, I've got a buddy that is putting a chevy 350 into a yj with some chevy axles. What we do know He's got a '90 yj islander that is puke green/teal colored. He's got the motor, tranny, and xcase mounted in the jeep now. Looks like a dana 44 chevy front axle, and a rear 12 bolt. The 12 bolt has 3.07 gears, but haven't opened up the front yet. What we don't know for sure 1. Wondering if we can hack into the yj wiring harness to hook the engine up to the dash etc.., but facing the reality that we will probably have to get a painless kit and use that. 2. Probably going to need some custom driveshafts, but were wondering if anybody knows of any that may work, front or rear. 3. Whether or not we need to shorten the front axle. The rear axle will stay the same length. The front axle though, will need to be shortened by about 1.5-2 inches to center it on the frame and use the cast spring mount in the differential. 4. Whether we can use the same steering setup that is available. Yj box, with either yj tie rod or use the chevy tie rod (probably depends on whether or not we shorten the axle. This is about it for now, but realize there is still a lot of work to do. Plans are probably to be finished either this fall or next spring, not real sure. Just depends on what needs to be done, and what kind of time and money he has to put into it. thanks for all of your help. BiggDaddy

01-21-2008, 08:11 PM	#9
BiggDaddy Join Date: Nov 2007 Location: Sidney, Ohio Posts: 52	thanks guys Hey thanks everybody. We'll take this advice and get on with the project. I'll try and snap a few pics next time I'm over so you can see how ugly this thing is. I'm sure I'll have some more questions for you sooner or later too. Thanks again. BiggDaddy

01-31-2008, 03:54 AM	#10
BiggDaddy Join Date: Nov 2007 Location: Sidney, Ohio Posts: 52	finally got some pics resized Here are some pics. Took forever to figure out software to resize them. Attached Images

01-31-2008, 10:38 AM	#14
BiggDaddy Join Date: Nov 2007 Location: Sidney, Ohio Posts: 52	Craigslist? no. Nope. It's a package deal they had for a couple of years. I think '90 and'91. Picked up the whole Jeep for $500 and a couple of cj axles.

01-31-2008, 11:38 AM	#17
JET455 Your wifes pimp! Join Date: Jan 2007 Location: Everywhere!!!!!! Posts: 548	Axles are 10 bolts the front will take 35's I would not go larger then 33's though casue the rear is a c-clip axle. __________________ if i am not currently offending you, i will be shortly.

01-19-2008, 11:01 PM	#2
94Dodge Truggy EX-Vice President Join Date: Jan 2007 Location: Fairfield, Ohio Posts: 3,048	You can hack into the stock harness but it will be a very long and tedious task where as the painless wiring will save u time. On the axle just relocate the perches and run a custom offset rims. Plan on having to resize the driveshafts. The painless wiring harness will be money well spent and the dash will be more functional. Good luck!

01-20-2008, 12:01 AM	#3
sarge Pure Bacon Join Date: Jan 2007 Location: Trenton, Oh Posts: 1,098	post up on miami valley 4 wheelers site . www.mv4w.com I think it's "teach " on their site that can splice your harness up in an afternoon so it all works just like it did stock .

01-21-2008, 10:49 AM	#8
blazerbrad - CORE Member - Join Date: Feb 2007 Posts: 831 Images: 6	As already mentioned, it would be much simpler to move the front spring mounts then actually shortening the axle, especially for just a couple of inches. I believe there are companies out there that even make kits for this.

01-31-2008, 04:02 AM	#11
muddinredneck513 Join Date: Jun 2007 Location: hamilton,oh Posts: 184	he get that jeep off craiglist? i seen one on there a while back just like it with the sun lookin thing on the door!! if not it was its twin!!!

01-31-2008, 10:56 AM	#15
94Dodge Truggy EX-Vice President Join Date: Jan 2007 Location: Fairfield, Ohio Posts: 3,048	Appears to be light duty axles. What size and brand tire do you plan on running?

01-31-2008, 11:47 AM	#18
94Dodge Truggy EX-Vice President Join Date: Jan 2007 Location: Fairfield, Ohio Posts: 3,048	Buy my 60/70 combo and be done! I also have a 30 front and 35 rear with 4.10 ratio from a 94 wrangler. Make me an offer!

01-31-2008, 11:57 AM	#19
carwash pimpin' IS easy Join Date: Jan 2007 Location: Union, KY Posts: 3,344 Images: 605	truggy is having one hell of an axle sale right now, that's for sure. __________________

01-31-2008, 04:02 PM	#20
blazerbrad - CORE Member - Join Date: Feb 2007 Posts: 831 Images: 6	Looks like a 10-bolt front axle to me. But whether it's a D44 or 10-bolt shouldn't make any difference because they are basically identical in strength. In my opinion that fact that the rear axle is a c-clip design is a moot point in regards to strength. The c-clip in no way makes the axle any weaker than if everything else was identical with the exception of the c-clips. Sure, if you break a shaft it can spit off the tire end, but so can a flanged (non c-clip) axle (I've seen two flanged D44 rear axles do this). But in any case they aren't exactly the epitome of beef in regards to axles, and the gearing sucks, but should hold up reasonably well under a light vehicle only running 33-35" tires. This also assuming they are in good condition, if the shafts and such have already been beat on hard for 20+ years then they would have a lot of fatigue life.

02-01-2008, 12:06 PM	#21
sarge Pure Bacon Join Date: Jan 2007 Location: Trenton, Oh Posts: 1,098	my old rig ( now Hybrids ) was on 10 bolts and I beat the crap out of it , never had a problem with the rear and it was welded. Started breaking fronts only after welding it up , I was running 35" boggers and a mild 350. Biggest mistake I made was going to a 14 bolt in the rear and still running 35's , it was worse then running 31's with the 10 bolts . " no clearance!!" I would run the 10 bolts and up to 35's for now. Get a couple trail spares and have fun. The 10 bolts are dirt cheap and easy to work on and easy to find in the scrap yards.