Toy swap Q's

[D Chapman]

If you're not using a double cardon shaft, the pinion and the t-case angles should match.
http://www.4xshaft.com/images/2joint_angle.gif

I had this issue on my truck but it was in the front with a 3" lift. I installed a double cardon shaft and all was well. There were no vibes, but I had an awful roar, or rumble, when off the gas, and it got really bad when coasting down a hill at speed (like on the Interstate).

If you did a Toyota swap you have a drive-shaft with 1310 u-joints. What kid of shaft do you have? GBR? What size lift you running? What rear trailing arms? Do you know your pinion angle? Is it greater than 3*?

 

[lforgue8]

If you're not using a double cardon shaft, the pinion and the t-case angles should match.
http://www.4xshaft.com/images/2joint_angle.gif

I had this issue on my truck but it was in the front with a 3" lift. I installed a double cardon shaft and all was well. There were no vibes, but I had an awful roar, or rumble, when off the gas, and it got really bad when coasting down a hill at speed (like on the Interstate).

If you did a Toyota swap you have a drive-shaft with 1310 u-joints. What kid of shaft do you have? GBR? What size lift you running? What rear trailing arms? Do you know your pinion angle? Is it greater than 3*?

Lift is a RTE 3" with 1" spacers....RTE rear links, stock rear drive shaft, pinion angle if i had to guess is less than 3*

ok so you had the same in the front off the gas rumble back on the gas rumbel again untill speed was increased.....like you could modulate the gas pedal and get it to happen?

im going to call TW and see if i can get a shaft before thurs night....i now i need one anyway

 

[D Chapman]

How did you do the Toyota swap and still use a stock Rover drive-shaft? Did you re-drill the flange or something?

Typically with a 3" lift the stock rear drive shaft is okay. When you get to 5" that's when issues start happening.

However, this may not be the case with the Toyota 3rd member. I can't recall if the pinion length is different between the Toyota and the Rover 3rd's, but you now most likely have a low pinion Toyota 3rd installed. Is that right? Or did you get a FJ high pinion 3rd? The RTE rear links are designed to correct the pinion angle of the Rover high pinion 3rd, but there should be enough adjustment available with the use of shims to dial in your new diff. Just keep in mind that your adjustments will be different with a high pinion vs what they'll be with a low pinion diff.

I'm starting to think your pinion angles might be off a cunt-hair. Get out your angle finder and take some measurement with the truck sitting on level ground. If you don't have an angle finder, download the app to your, or your friends, iPhone. I think this is going to be your first step in finding your issue.

The only other thing I'd check right away is the big 30mm nut behind the e-brake drum. I've seen these come loose and cause issues such as this, but it does not take long to get worse.

 

[lforgue8]

the 30mm nut is fine new seal and nut not to long ago and no noises before toy swap....yes Keith redrills the toy flanges for a rover pattern.... i will have to see the angles tonight i do have a angle guage.....pinion lengths may be slightly longer on the toyota but by how much im unsure and it does sit lower than the rover diff for sure....i played with the link shims already to get the driveshaft straight with the diff so was i wrong to do that?

if i point the diff down anymore i would think i would have binding at the tcase end so i chose a happy meduim. would i need to come up with the diff i dont see how that would work either.....ive seen the pics on TW site and i think its just time for a new dc rear shaft... i dont think there is any way id be able to get the diff center line parallel with the tcase.....ill also try to snap some pics of how it looks too

 

[lforgue8]

So it looks like i have 5* between the diff and the shaft.......the tcase sits at 0*

so im unsure what to do here ill have to search pirate and stuff to read up on that

pics: 1st is just pic with out gauge
2nd is diff reads 10*
3rd is shaft reads 15-16*

 

[lforgue8]

pics: 1st is tcase reads 0*
2nd just another of the rear end

 

[Steve Rupp]

That angle is way off for a standard shaft. You're going to need to get a DC shaft for the rear and pull out some shims on the links if you have them to raise up the diff a little more. That angle looks pretty steep already to lower it and use a standard shaft.

 

[Steve Rupp]

Also you should be measuring your angles without the driveshaft on. Measure each flange. The angles should be the same putting that pinion much lower.

 

[Mike_Rupp]

If never fails to amaze me how far people can get into a project without understanding the basics of how driveshafts work properly.

Read this:http://www.4xshaft.com/driveline101.html

 

[KyleT]

get a digital angle finder.... i used one of those and had it dead nuts for caster and when it was all said and done, i was at 7.5* on the right and 12.5* on the left with the digital one i should have used the first time....... so now i get to recut the knuckle balls and reweld them....

edit, my rear is pointed directly at the t-case and i have no vibes or noise. rrc swb driveshaft on my d2.

 

[lforgue8]

If never fails to amaze me how far people can get into a project without understanding the basics of how driveshafts work properly.

Read this:http://www.4xshaft.com/driveline101.html

im so sorry i dont know everything....and i like it how you say it so generally, not towards me........i still dont know if this is my noise, as i said earlier i knew my driveshaft angle wasnt ideal but am still unclear if its my noise.....i dont understand how this drive shaft that was ok before is now making so much noise after just installing the toy diff.........on the highway about 50-60mph it is very loud....on the lift at work let the load off and the noise is pinpointed right at the pinion so im still unclear as to how a driveshaft could transfer noise from the tcase end where its quiet to the pinion bearing area.......its not known if the diff case is warped or what causing the bearings to "unload" because the bearing arent spinning true...........i already admitted that i dont know all there is to know about this so thanks for the link and i WILL read it

 

[lunchbox]

I told you from post one that it was your DS. I still think it is your DS. I have your same set up. Pull the DS and go for a spin. See what happens. The reason for the change is the third. The toy third is at a different angle than the rover one. It sits in the axle housing in a different position, throwing your angle off.

 

[Steve Rupp]

Luc, I think what everybody is telling you is to get your pinion angle squared away before go any further. You're going to need to do it anyway and it might be a simple solution to your problem. You do understand that the angles are completely wrong right?

 

[lforgue8]

I realize and appriciate all the suggestions from all of you and have read up the articles on TW's site and have seen some more info and found that i do need to fix the rear diff angle to with-in the 3* "rule" and get a cv shaft and i will do that first.....ill have to see if the noise is lessened...........

just for conversation sake though, say the noise is lessened but still there and found to be in the pinion area of the diff only.....also consider that the set up is good what would need to be out of alignment to cause a rumble in the pinion.......i know adjustments in building a diff are measured in the .001 or smaller so i feel if the bearing race "stops" or shoulders are out would that make noise? also wouldnt the setup be affected?

 

[BCA93rangeroverlwb]

IF it is not your driveshaft (not saying it isnt). It could very well be your adjustments on your diff. check the coast side of the ring gear aswell as the backlash IF you need to pull your diff.

Also a guy you can talk to about toy diffs if you need it http://gearinstalls.com/

 

[lforgue8]

IF it is not your driveshaft (not saying it isnt). It could very well be your adjustments on your diff. check the coast side of the ring gear aswell as the backlash IF you need to pull your diff.

Also a guy you can talk to about toy diffs if you need it http://gearinstalls.com/

I read almost every install on ZUK's site and followed just about every suggestion he has on there and im pretty sure that the setup is right.....again i have a few more people going to listen to the noise and maybe even get a vid of the noise and post it

i am going to fix my driveline situation though!