dana 30 swap question.

i finally got the dana 30 into the '71. the question i have is when i get my degree wedges from mike what way do they go on? it looks like to me that the axle needs to rotate towards the front of the jeep in order for the drive shaft to line up better with the transfer case. my jeep has a lift kit (not sure how much) and there was not any wedges in there when i took the axle out. sorry for such a newbish question as i'm not an expert on driveline angles. i will be bringing it to the alignment shop hope fully this week to fish the job out.
the other question i have is the residual valve. that can go anywhere in the line after the master cylinder?

 

The thick part of the "wedge", commonly referred to as a degree shim goes toward the rear of the Jeep. This is to rotate the top of the axle rearward. The reason is NOT the pinion angle for the driveshaft/u-joint but to increase caster for drive ability purposes. This will help with tracking, reducing instability (death wobble), reduce wandering, etc.
correct installation of the shims will actually increase the driveline-u-joint angle on the front but unless you have 6" or more of lift should not be an issue.

Regarding the residual pressure valve, it's recommended to install it as close to the master cylinder as is reasonably possible.

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thanks for the response nick. i think that i have a 2.5" lift maybe more. i didn't install it so i'm not sure that's how i bought it. i know there are some shims between the cross member and the frame maybe 1/2" or so maybe less and i think some body lift too. my shackles are 2-3/4" center of bolt hole to center of bolt hole so i'm not sure if that is stock or not. i thought that the thick side would face the rear but what i was thinking was incorrect.

 

This is backwards for spring-under. Tilt the top of the knuckle back to increase the caster angle. This means the wedge goes on top of the spring with the thick part to the front.



IMO the suspension geometry you have after a lift is at best a guess. You need to finish the lift and have your local tire shop do an alignment. They can set the toe-in and center the steering as part of the alignment. Ask for the printout. Then adjust the caster angle with shims to get in the proper range.

Ignore the pinion angle on the front axle. The Jeep needs to be drivable, and you have to take care of that first. The only way you can correct the pinion angle on the front axle is to remove the knuckles from the tubes and weld them back in a new orientation.

 

Oops, brain fart on my part. Tim caught me and is right. Thick part to the front to increase the caster angle. Do you know what your caster angle is now? If about 4* or less I would increase it to 5*-7* positive (top of knuckle angled back. Factory spec was 3* but that was for stock size tires. 5-7 works much better for larger than stock tires.
You can do a rough caster angle check with a cheap angle finder. Not super accurate but would give you an idea where it's at. The most accurate way would be Tim's suggestion and have it checked with an alignment machine. They could check toe at the same time.

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ok another newb question. where do i put the angle finder? the most ideal location?

 

Bottom of lower ball joint has worked for me since it's nice and flat.


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I have had good luck with 5 degree wedges on my 78 D30. I was concerned about too much pinion angle so I went with 5 degree instead of 6 or 7.

 

it does look weird seeing pinion going down, one would assume it should go the other way. to make the driveshaft angle better.

however, going from only able to do about 30 mph with issues to doing 65 mph with a lift and toe slightly off tells you yep castor shims work.

I personally still do not have a front driveshaft because pinion angle changed. my jeeps a special case because the previous owner didn't route the passenger exhaust correctly,


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ok will do nick. i think i need to buy one as mine is mia.

 

so let me get this right. lets say the angle finder reads 4* so i would need a 2* shim to get the 6*?

 

i agree it does look wierd with it pointed the other way. hopefully the driveshaft is going to be at a good angle. if i remember right i always heard 11* or 15* is the max you want on a driveshaft unless you want to eat u-joints all the time.

 

got everything from mcruff bolted in and nice and tight. i installed the residual valve about a foot away from the master cylinder. is that going to cause any issues and it is installed in the vertical position as the po had made a connection there and was the closest to the mc. i bled the brakes and might do it again tomorrow as i think there is some air in there yet.
i drove it down the street about 5-10 mph and hit the brakes. pulled hard to the left and then right for a few times and then cleared out. i do notice when i am in reverse and hit the brakes the fronts will half lock up is this bad? after i bleed the brakes again tommorow i ill hit the brakes even harder to test a panic stop. i am running a dual mc but it was what autozone had for a '71 listed and if i remember right i removed the valve (at least i think i did) way before i did the conversion. this was almost 7 years ago i think. what will happen if that valve is still in the mc and me running the residual valve?

 

steering with the dana 30 is much nicer than the 27, even with the two piece mod instead of the three piece stock steering on the 27. i cannot wait to get the front driveshaft shortened and the front yolk on the t-case so i can see what these 4:27 gears are going to be like. so far i wish i would have gotten the 4:88's instead of the 4:27's. it wasn't until i had both axles re-geared and put back in the jeep when i found a set for both axles.

 

i drove it again today up and down my road. in reverse when i hit the brakes it really wants to pull to one side or the other, but in forward it's nice.

 

i hope to bring my driveshaft in on tuesday and have it shortened. i pulled it from a '74 cj5.

 

#1-- i installed the residual valve about a foot away from the master cylinder. is that going to cause any issues as it is installed in the vertical position?
#2-- i do notice when i am in reverse and hit the brakes the fronts will half lock up is this bad?
#3--what will happen if that valve is still in the mc and me running the residual valve?

 

First of all, you are running drum brakes all around right? We just know you switched some stuff don't know if its drum or disk.

 

doh! sorry. this is a '74 axle with '78 knuckles out with the disc brakes.
piffey did you buy a new tierod when you installed that 30? if so do you have the part number? i tried looking at napa's and autozones websites and the picture does not look right. i'm talking the one from a dana 27 to the bellcrank tie rod. the one with the hole in it.