Jeep Wrangler Forum

Jeep Wrangler Forum (http://www.wranglerforum.com/)
-   TJ Tech Forum (http://www.wranglerforum.com/f210/)
-   -   t case drop (http://www.wranglerforum.com/f210/t-case-drop-47299.html)

dasaffen 03-23-2010 06:24 PM

t case drop
 
Hey all. I recently installed my 2.25 inch bb. Unfortunately I am getting drive line vibes. At this point I know I need to drop the t case. My question is, how exactly do you drop it? Any write ups and pictures would be awesome. Thank you in advance.

4Jeepn 03-23-2010 06:50 PM

You can either buy a kit, or use washers to lower it, but you can only go so low with the stock bolts.. But either way, loosen all bolts and have a jack under the skid plate and one under the trans as a just incase. Then remove one side of bolts at a time..insert washers or new hardware, to include new bolts an spacers and snug up a bit then do other side. Then tighten all. You may/will need to adj the t-case shifter linkage as well. Small adjment screw towards rear you will see.

sj pat 03-23-2010 07:03 PM

Just did a 1 inch TCD on mine and it helped but did not get rid of all the vibes

Jerry Bransford 03-23-2010 07:09 PM

Quote:

Originally Posted by sj pat (Post 580051)
Just did a 1 inch TCD on mine and it helped but did not get rid of all the vibes

For what size suspension lift? Normally it only takes 1/2" to 5/8" t-case drop or so for a 2.25" suspension lift.

sj pat 03-23-2010 07:13 PM

3 inch

dasaffen 03-23-2010 07:19 PM

what bolts am i placing the washers on? sorry i know its a stupid question but i really dont know what im doing lol

03 RUBI 03-23-2010 07:51 PM

You put the washers between the frame and the skid plate so as to lower the skid plate.

Jerry Bransford 03-23-2010 07:55 PM

Quote:

Originally Posted by 03 RUBI (Post 580105)
You put the washers between the frame and the skid plate so as to lower the skid plate.

Just one more step to add to the advice... loosen all six bolts that hold the transfer case to the frame but once you have the jack supporting the skidplate, only remove the bolts on one side. Insert the washers & bolts & loosely thread those bolts back in. Then do the other side. Keeping the bolts in one side helps keep it aligned for less trouble putting it back together again. Use the jack to lower it down just enough (one side is still loosely bolte in place) to insert the washers so you get enough drop. Raise the jack up enough to thread those bolts back in and then repeat for the other side. :)

dasaffen 03-23-2010 10:18 PM

ok thank you for all the help

Kevin 03-23-2010 11:16 PM

T-case drop
 
I recently put a 2" lift on my 98 TJ Auto and found that I had a low speed vibration in the drive line. Driving it locally in the city when I added a little power it vibrated but when it leveled out the vibration went away. I Went to 4-wheel drive to get what I needed to drop the skid plate and they wanted $68 bucks plus for it. I told them I would build what I needed and he reminded me that I would need longer bolts. I went to a local farm implement mfg and they had the grade 6 1/2" bolts with allen heads but matched the bolts we removed. This is what we did. I had 1X2"X120 stainless tubing in the shop, matched up the holes & installed it. It solved the vibration problem. The so-called 2" lift actually lifted it about 2.5" but I understand it will settle some. http://i833.photobucket.com/albums/z...TOBUILD007.jpg[IMG]http://i833.photobucket.com/albums/z...TOBUILD012.jpg

03 RUBI 03-24-2010 12:46 PM

Jerry, you,ve got the right way to do it. I was just answering his question about where to put the washers.

dasaffen 03-25-2010 11:32 AM

thank you guys I dropped the t case about half an inch yesterday. It took about four grade 8 washers on each bolt and only cost me about 8 bucks. The vibes are completely gone now. Thanks again for the info.

IslandTJ 03-25-2010 12:54 PM

Quote:

Originally Posted by dasaffen (Post 581611)
thank you guys I dropped the t case about half an inch yesterday. It took about four grade 8 washers on each bolt and only cost me about 8 bucks. The vibes are completely gone now. Thanks again for the info.

I ran this solution for a while (took me 4 washers/bolt) and when I upgraded to 33" tires I installed a 1.25" bodylift and 1" motor mount lift from JKS. The motor mount lift allowed me to lift my transfer case skid back up to the stock position.

dasaffen 03-26-2010 12:34 AM

ow much did the motor mount lift run you? and how easy/hard is it to install?

IslandTJ 03-26-2010 11:39 AM

Quote:

Originally Posted by dasaffen (Post 582314)
ow much did the motor mount lift run you? and how easy/hard is it to install?

I installed a budget motor mount lift (MML) which is basically a 1" spacer under the OEM motor mount. The MML was bundled with a 1.25" body lift but it may be purchased separately for roughly $50.

To be honest, the installation was one of the most difficult projects I've had on the Jeep, but to be fair, I tackled it on my own. Definitely helps to have a second pair of hands.

Jerry Bransford 03-26-2010 12:30 PM

While I won't say it was "easy", I've installed two sets of motor mount lifts into my TJ and I was done in an hour with both of them, only one of which did I have help on. One of them was the first set of motor mounts I had ever installed when the engine was still in the vehicle. All you really need is a hydraulic jack & a 2x4 to support the side of the engine you're working on. :)

FrankTheTank 03-26-2010 02:28 PM

I have asked this before but want to get confirmation one more time you can go to 4" lift on a Unlimited with out a t-case drop?

pking911 03-26-2010 02:48 PM

I think even a lift as low as 2.5" might need a tcase drop. I am unsure of the LJ though.

IslandTJ 03-26-2010 03:01 PM

Quote:

Originally Posted by pking911 (Post 582783)
I think even a lift as low as 2.5" might need a tcase drop. I am unsure of the LJ though.

No definite standard, I required one with just a small lift of 2".

Jerry Bransford 03-26-2010 03:10 PM

Quote:

Originally Posted by FrankTheTank (Post 582768)
I have asked this before but want to get confirmation one more time you can go to 4" lift on a Unlimited with out a t-case drop?

Your LJ's significantly longer wheelbase lets you lift taller than a TJ without vibrations and 4" pretty close to the limit where most LJs do ok without a t-case drop. But there's no hard fast rule, your LJ may or may not need a slight t-case drop at 4" of suspension lift. Fortunately, that is a minor inexpensive easy thing if it is needed. :)

jpconard 03-26-2010 06:20 PM

I just ordered my 2.25" budget boost for TJ I had since last June. Should be here Monday so I'll prepare this weekend by dropping the skid plate to make sure it comes loose. I've been trying to hit the weldnuts inside the frame with PB blaster last couple of days. Plus I need to check the transmission mount and change t-case fluid (ATF-4).

Two questions -
1) For anybody who has done only a 2" BB lift, is the alignment actually off after installing the lift?

2) I don't understand how a does a motor mount lift allow the T-case to not be dropped. lift will raise the T-Case and motor together. The vibration issue is from the T-Case to rear differential, correct? Does the motor become angled differently or something after the motor mount lift? I don't plan on motor mount lift, but just curious.

Any additional tips would be helpful, I've read many online write-ups, so I have plenty of information, I believe.

jpconard 03-26-2010 06:26 PM

Also, I've googled and searched various forums, but are there any good resources for shock length requirements (compressed length, extended length) for different lifts? For example with a 2" BB what is the recommended shock lengths, versus stock? I've read stock can be used, but what do I lose (articulation)?

Are OEM replacement shocks (Monroe or equal) available at local parts store (Autozone, Oreilly) that work good for a 2" BB lift?

Jerry Bransford 03-26-2010 06:46 PM

Quote:

Originally Posted by jpconard (Post 582908)
1) For anybody who has done only a 2" BB lift, is the alignment actually off after installing the lift?

2) I don't understand how a does a motor mount lift allow the T-case to not be dropped. lift will raise the T-Case and motor together.

1) Yes, a suspension lift increases the amount of toe-in plus you will have to straighten the steering wheel. No worries on the caster or camber angles though. You must adjust the toe-in back to within specs or your front tires will wear far more quickly.

2) A MML doesn't so much lift the engine as it tilts it to a steeper angle, so the front is higher but the rear is at the same height. That steeper angle better matches the driveshaft's steeper angle caused by the suspension lift. Excessive angles where the transfer case connects to the driveshaft is what causes vibes so by tilting the engine/tranny/transfer case assembly steeper, it better matches the steeper driveshaft angle which stops the u-joints from vibrating.

Kevin 04-20-2010 01:13 PM

Need help
 
After reading the threads have decided to do a 1" motor mount lift on my 98TJ.:crash: I did the skid-plate drop after installing a 2" lift and it worked fine but I'd like to raise the skid-plate back to it's normal position.:rolleyes:

1. Is the JKS lift good enough or would you recommend another?
2. Will this create a problem for the fan shroud?
3. It looks fairly straight forward reading the above threads but should I expect any surprises?:confused:

Appreciate any help with this project.:wavey:

IslandTJ 04-20-2010 01:45 PM

Quote:

Originally Posted by Kevin (Post 603221)
After reading the threads have decided to do a 1" motor mount lift on my 98TJ.:crash: I did the skid-plate drop after installing a 2" lift and it worked fine but I'd like to raise the skid-plate back to it's normal position.:rolleyes:

1. Is the JKS lift good enough or would you recommend another?
2. Will this create a problem for the fan shroud?
3. It looks fairly straight forward reading the above threads but should I expect any surprises?:confused:

Appreciate any help with this project.:wavey:

  1. The JKS solution, provides a 1" spacer that allows you keep your stock motor mounts. If your OEM motor mounts are worn or broke, most ppl elect to use M.O.R.E. or Brown Dog for outright replacements.
  2. You will have to relocate your shroud, this is easily done by drilling new holes.
  3. You may need a bracket for your transfer case shifter as the motor mount lift may raise the drive train enough to impact 4WD shifting.

Numbers 2 & 3 may be mitigated by adding a bodylift.


All times are GMT -5. The time now is 09:21 AM.