Lowering transfer case after lift?

[Eric Winkworth]

I've been searching around for information on drive line noise/vibration after a 3 inch OME lift and although there are a lot of complaints about this no one seems to talk about a fix... Other then U joints and drive shaft balancing which aren't my issue. I can tell that the angle of my front drive shaft is what is causing it... I would like to be able to use 4 hi in winter situations where I would like to at least go a reasonable speed like 60kmph without vibration... Right now the vibration starts around 30kmphm I can only really hear anything when decelerating... I had thought I maybe had a differential issue, but after draining the fluid I had in there for a few years, it's pretty darn clean even with quite a bit of 4wd use...

So my thought is lower the transfer case an inch? Ground clearance is limited more by differentials anyway so whats the harm? Now I do need to find some 1 inch spacers to do the job.

What are people's thoughts and opinions? Any idea's on where to source such spacers? What kind of material should they be?

Thanks for any replies
Eric

 

[Radd Cruisers]

We have done lots of lifts on Land Cruisers over the years, and many are greater than what OME gives - the vibration is not likely caused directly by the lift, you have other issues there that are causing the troubles. But do check your u-joint operating angles carefully - there can be some difference between each end of the shaft, but it should not be that substantial (a few degrees).

I personally drive a lifted HZJ77 and a lifted BJ74 as well as an HJ61... the front driveshaft length in these vehicles is all about the same. There are no vibration issues where the vehicles have low mileage and are in great shape. Once there is some wear, the noise starts to show up. There is some starting to show up in my HJ61 at 240,000 kms and a little started to show up in my BJ74. The HZJ77 being much lower mileage is a smooth as silk.

The vibration that you're feeling - a sort of buzzing or growling on deceleration is most likely a combination of things - driveshaft spline wear, u-joint wear, and transfer case lash/bearing tolerances that are going out.

My belief is that when you get two more sources of play due to wear, even if they are relatively small, you can get quite loud noises being produced.

You can try a few things to get rid of this: make sure that your driveshaft spline has no play; make sure that our u-joints are new, and that your driveshaft is in phase; make sure that your transfer case output bearing (front) is in good order; make sure that the transfer case output shaft is preloaded properly and the bearing are healthy; make sure that the torrington bearing that supports the front output stub shaft on the inside end is in good shape.

Then check that your pinion bearings are in good shape, any roughness or play and they should be replaced. I would suggest that you set them up with a hard spacer when you replace the bearings.

Hope this helps.

John

 

[Radd Cruisers]

Oh, and spacing the transfer case down will actually make the rear joint/front shaft angle steeper.

~John

 

[Eric Winkworth]

Good to know, thanks. I would have never thought that lowering the transfer case would make the joints steeper...

Anyway I'm into a lot of other things on the truck right now so I'll have to add some more parts to the list... Both drive shafts are JDM ones from G&S, both are in amazing shape, no play in the splines, nice smooth u joints no tight spots or play... It made a huge difference when bogging the engine 2wd when I replaced the rear shaft... The truck has just over 310 000km and I can't imagine anything has been touched. I did a knuckle rebuild a few years ago but other then that just fluid changes....

Having said that what would you suggest? Could you supply the parts? What would the cost be?

Thanks for the reply
Eric

 

[gagnier]

Have you tried greasing anything then taking it out for a drive? Grease front u joint, then drive , no change, try greasing the slip yoke, and drive etc.? Worth a try I would think even if they are in great shape its somewhere to start.

 

[Capitalguy]

Did you install the metal wedge in between the front axle and leaf springs, ( the official part name escapes me right now) and is it the correct angle for you application?

 

[Eric Winkworth]

I've greased everything a bunch of times no change...

I'm thinking of going for double cardan joint shaft and just selling the shaft I have.. From what I've been reading a lot of people have this issue after lifts on SWB 70's.

You'll have to be more specific on the wedge, I did the lift several years ago, Don't really remember a wedge between the front axle and leaf springs... The only spacers I remember were for castor on the knuckles.

 

[Capitalguy]

They are called front axle shims, use mudsearch. My connection isn't the quickest here so I can't help you with any direct links

 

[Capitalguy]

Try this link below, go to post #21, it's for a 60, but same idea, also mudsearch front leaf shims

Shim question on leaf packs
60-Series Wagons Tech talk for the 60, 61, and 62-Series Cruiser wagons -- FJ62. com .... 4Crawler Offroad Products - Custom Leaf Spring Shims ..... When you increase the front shackle length on an FJ60 you are reducing ...
forum.ih8mud.com/60-series.../198745-shim-question-leaf-packs.html

 

[Eric Winkworth]

After my own reading around the forum on the 80 forum a lot of ppl talk about going to double cardan joints for front drive shafts because of vibration issues after lifts... Also I can't see how my diff could be positioned to make the angle any better the diffs drive shaft face points directly at the transfer case face... 60 series trucks are said to have come with DC front drive shafts... Other LC's like mine didn't, however it sounds like a good way to fix it and I have a line on one out of a 70 series that someone had a lift on and had it made the truck is now being parted out... If I can undo 8 nuts and make it so I can go 80kmph again in 4wd it's worth a couple hundred bucks in my book... The shaft I have looks new and I can prolly get 100 bucks out of it...

 

[Eric Winkworth]

Capitol guy does your 70 series have any vibration with your lift?

I have herd in the past vibration is pretty standard after a lift on these trucks...

https://forum.ih8mud.com/80-series-tech/199148-double-cardan-drive-shaft-solutions.html

 

[Capitalguy]

I installed the OME lift well over a year ago and have never had any vibrations, even when I wheel off road with it, then air up and drive highway speeds back home, never a vibration. Radd sold me the kit. The shims are fairly inexpensive, order a set and see if it cures the problem.

 

[Eric Winkworth]

Do you drive highway speeds in 4 hi? That's the only time I would ever notice anything....

Where did you buy the shims?

 

[Capitalguy]

I've had it up 60 kph +/-, a few times in the winter, but for the sake of mud research this weekend I'll bring it up to 80 kph in 4 high on a straight stretch of road and let you know.
Any local spring shop should have them. I don't remember how many degrees the one in the kit was, maybe someone in the know could chime in a make a recommandation

 

[Malahki]

My OME lift with extended shackles came with 2 1/2 degree shims. The rear ones are for pinion angle but the front ones are for castor angle. I made the mistake of installing the fronts as pinion angle shims and the on road handling was horrible, with lots of wandering and bump steer. I flipped the shims around and the handling was night and day. In fact I have since went to a 4 degree castor shim with a noticeable improvement in handling.

Consider you loose at least a couple degrees of castor with the lift and you'll loose a couple more using pinion angle shims. Now your castor is going to be out up to 5 degrees over factory specs. Not good!

The only real way to correct the castor and the pinion angle at the same time, is to do a cut and turn on your knuckles, with either pinion shims or repositioning the axle perches

 

[Eric Winkworth]

Good to know, I was doing some reading on the 4 crawler website last night about this exact thing...

I know when I did the alignment after the lift everything was to factory spec's and they checked castor... I can't complain at all with how the truck handles at speed. However it's not smooth in 4wd when going fast... I just keep looking at the u joints angle out of the T case and thinking there is really no way of making that angle better without lowering the truck... So I really do think DC drive shaft is my fix. Let the DC joint do the angle and the U joint at the front diff is fine...

I am interested to know what every lifted 70 owner experiences at speed in 4 hi though!

 

[Glenn-BJ74]

My 74 has vibration at high speed in 4 high (above 40 mph), but if you look at the transfer output angle (slightly up) and and front pinon angle slightly up or flat) they a long way from being parallel. I put in 4 degree of castor correction (reduces highway wandering with the 315s), which tilts the front pinion angle down getting it closer to parallel, but it is still a less than ideal set-up.

In my 74 I don't have clearance for a double cardan joint, so I avoid using 4-hi at high speed.

 

[Eric Winkworth]

Thanks for the input

I've avoided high speed in 4hi now for several years and the only time I ever really miss it, is in the really big dumps of snow we get a few times a year here in my part of southern ontario... It's just nice to have the option after all it's a big part of why I bought a 4wd truck!

 

[Capitalguy]

Eric; had my truck out today in 4 hi on straight stretches of road doing 80 kph, no vibrations.

 

[Eric Winkworth]

You must have some nice solid bearings in the t case out put and diff input... I think it's more uncommon from talking to people and reading around on the forum to not have vibrations after a 3 inch OME lift... Congrats I wish mine was smooth as silk...

Here is a blurb on the truck I'm getting my double cardan join drive shaft out of....

PS: You will no doubt notice, but I forgot to mention, that the the front driveshaft is a little bit different than typical for a 70 series. The shaft is a double-cardan type from a BJ60 shortened to fit the 70. The truck originally came with the stock single-cardan shaft that made it undriveable in 4WD due to the angles created by the suspension lift (3 inch OME). Once I changed out the shaft, it ran smooth as silk at highway speeds in 4WD.