Planned DII mods, looking for feedback.

[davebrown]

Hello all. I have not posted much in the past, but I?ve spent a lot of time reading posts here, learning a lot, getting many opinions and ideas. I?ve compiled a list of modifications for my truck that I feel will fit my particular style of off-roading and driving habits. I?d like to get some opinions (which I know D-web is never short of) on my plan.

First, some background/operating framework:
-Vehicle specifics: 1999 Disco II, ABS, ETC, HDC, no ACE.
-The truck is my daily driver and sees 99% street use, so it must remain well-mannered on pavement.
-While I freely admit that some of these mods are more aesthetically motivated than functional requirements, my primary goal is to make the truck more robust for medium-duty off roading. (Understanding that the vehicle is probably tough enough right out of the box for what I normally do, I still want to beef it up a bit.)
-My garage door is relatively low, so I have only about 5 inches of height to play with.
-During the summer, I regularly tow a camping trailer that weighs ~3500 lbs.

Here is the plan?

Suspension/Tires:
-OME spring upgrades; 779?s or 751's in front, 781?s or 762's in back. Matched 751/781 with rear "hockey puck" spacers from EE seems to be a popular combo. As I understand it, this spring/puck combo gives approx 1.5" of lift and levels the vehicle out.
-This will in turn allow for fitment of 265/75-16 tires. I believe that this spring/puck/tire combo gives about 3-4" of overall lift.

Drive-train:
-TrueTrac LSD for both front and rear diff?s. It looks like several folks have had good luck with the TT and ETC combination for non-extreme off roading.
-GBR HD axles, although maybe not right at first. I believe for the DII, they are only available for the rear at this time. If somebody knows of an HD front axle set for the DII, I?d be interested to hear about it.
-I will likely replace both stock drive-shafts with GBR units.
-Also, I plan to fit some type of CDL handle, whether that be a retro-fitted DI T-case shifter or one of the ?homegrown? solutions that I have seen posted here.
-Question: Will the above tires require a change in gearing? I was thinking of going to a 4.1 gear set, but some articles suggested this was only necessary if mounting a 33? or larger tire.

Misc:
-Rock sliders
-Front skid plate
-Fuel tank skid plate
-Diff guards
-Hidden winch mount and winch.

Okay, there?s the plan, flame away!

 

[Disco Mike]

Bill at Great Basin has the HD ront axle also. 4:11's are really nice if you do alot of off roading. On the road, your gas mileage will be lowered by the 265's as will your power. You will need to make that decision per your driving habits.
Save your self some labor and wait on the lockers and axles untill you decide on the gears, no since tearing down the diffs twice.
I have a TT and a rear Detroit with 4:11's and CDL and it is nearly unstopable.
Have fun building up your truck.
Mike J.

 

[Croakus]

I have a 2001 Discovery with the 3" OME lift from EE. I've also got Rovertym bumper with skid plate, Warn 9000i, sliders, and a custom rear bumper from 4x4 Armor (I'll post some pictures of it later). Not to mention CDL and 265/75 tires.

I have not re-geared my differentials and have major problems on the Interstate. These aren't even MT tires, they're Yokohama Geolander AT+II's. Heavier tires would make it even worse.

If you intend to go to a tire that large, I highly recommend you go ahead and get the 4.11 gears (might as well put a locker in there while you have it open). Otherwise it will feel like someone put a 4 cylinder engine in there every time you go up a hill on the Interstate. Mine hits 4000 RPM's on most hills just to stay above 60.

 

[bigred]

I am running 33's without having regeared yet, and it isn't a big deal at all. I plan on changing eventually, but it isn't a priority.

 

[LostInBoston]

It sounds like your ready to build a great truck and have a great idea of what you want. I had 33" AT's with stockl gears for a while. Sure performance sucked and so did MPG, ut i got used to it. With the 4.10's you should pick up both performance and get some better MPG's. and also be able to tow. I gained about 1-2 MPGs after i regeared. Also, get them at the same time. I did diffs, but had an 8 month wait for the gears, so i tore them down twice which was a PITA. do it all in on long weekend. I dont think youll need HD axles with just dual TT's. although (this is gonna start another debate) i would just go with the detroit in the rear, ifyou alredy plan on getting HD axles. I have had no one road difficutlies or even notice tat tere is a locker int he rear when im on the road. ETC is great, when it works, but ive onle seen one truck with it, where it hasnt failed. mine always failed. and a couple other d2's ive wheeled with all lose it. Dean B is the only one i know of that has fully functional ETC, but he;s also a great driver and somehow find the lines that get him through, or flooded every now and then. OME is a good spring choice, migh want to check out RTE also. No winch bumper? i think they look better then stock bumpers and add some protection to the front. For the cdl handle, Ive read that the D1 style can cause some noise int he cab, so if its a daily driver you may not want that. I have the Cable kit, which personally i dont think is worth what theyre asking for it now, ubt still works fine, except the knob sometimes gets in my way when im crawling out of my window. If you have the $$$, pony it up for an electic solenoid one. I think GBR maystill have them. The GBR driveshafts are great, but might not be needed with only a 1.5" lift. although sometimes that just randomly blow up, so i think everyone should get rid of their stock units, at least in the front.

-Rick

 

[craig]

The GBR driveshafts are great, but might not be needed with only a 1.5" lift. although sometimes that just randomly blow up, so i think everyone should get rid of their stock units, at least in the front.

The front driveshaft in the Disco 2's is fine. The only reason to upgrade is to get the serviceable u-joints. It was the D1s that had the front driveshafts that got tweaked when they were lifted. The rear driveshaft will eventually show wear in the rotoflex. The GBR rear driveshaft replaces the rotoflex with a double u-joint.

I have the AMV solenoid which works fantastic. I have seen one other kit (can't remember where) that has a better location for the switch. Also, the AMV kit is designed for right hand drive vehicles, so you will have to extend some of the wires to get it to install on a left hand drive vehicle (not a problem though).

--Craig

 

[alex]

I would go for full lockers right off the bat if I were you. You will most likely want them eventually anyway. Why pay for things twice? ARB/ARB if you have the cash, or ARB/Detroit if you have slightly less cash.

 

[davebrown]

Thanks for all the ideas and input. I'll check with Bill at GBR about the front HD axles, last time I emailed him, he didn't have them yet, but that was a while back. I think I'll also wait to see how I like the stock gearing on the new tires for a little while before I decide on the gears. It sounds like some of you run much bigger tires on the stock gears with no real problems. Whichever way I go, I'll definitely decide about gear ratios before I do the diff change so it can be done at one time. Thanks for the info about the RTE springs, I'll give them a look too. I've kind of been back and forth on the winch bumper. I like the look too, but it's ~$800 for something I'm just not sure I'd utilize that much. I might put one on later. (Of course, the first time I'm grill deep in mud and I complain about trying to fetch the winch cable from under my stock bumper, you can all say "told you so!" ) I'll also give some consideration to putting a locker in back instead of the TT. Although, it sounds like if I just do the TT's front and rear, I may not need the HD axles.

Thanks again!

Dave

 

[gadams]

Dave,

Sounds like a great plan, I hope my end product gets somewhere close to what you are working toward as well. After a lot of advice, I am adding sliders earlier than later. Gearing, axles, lockers, shafts, lift are all great and needed but as my friends rightly pointed out, protection keeps you from crying when you should be laughing.

Greg

 

[gooddoggomez]

Dave

I have a 02 TD5 and have done the HD OME front and back, 265/75's BFG MT's and also have the ARB winch bar with a Warn XD9000 up front. I haven't explored the spaces yet, but am looking into it. Ideally I'd like to find someone here in Oz to knock some up for me rather than get lumps of alloy shipped half way across the globe (image explaining these things to some customs agent in this day and age).

I'm loving the suspension as is but the driveline really feels the 265's (the TD5 doesn't have as much poke as the V8) so I would definitely change to the 4.11's if the financial controller would let me.

As for the lockers, a really good ARB/ARB set-up can't be beat. As mentioned, its ideal if you have the cash. Since your rig is a daily as well TT's or detroits would be a drag in my opinion. Something totally selective is the answer for me, also in a similar position. Some people will say that your stuffed if your compressor goes etc - simple, feed a small tank with that compressor, so if it goes at least your still have something left. Or just buy a more heavy duty compressor than an ARB. There are heaps of more heavy duty compressors on the market over here, just like everything else, they just cost more. Check out compressors like Big Red and Blue Tongue (I think). These things are built like a Sherman tank.

Anyway mate, good luck and remember, keep it shiny side up.

Greg

 

[davebrown]

Thanks again for the additional ideas. I forgot to ask LostInBoston last time... you mentioned that you have seen a lot of ETC systems fail. What exactly about them fails? Do they physically break, (like a brake line, etc.) the electronics crap out or just continue operating with less and less efficiency? Just wondering if there are any signs I should be on the lookout for.

Dave

 

[LostInBoston]

Thanks again for the additional ideas. I forgot to ask LostInBoston last time... you mentioned that you have seen a lot of ETC systems fail. What exactly about them fails? Do they physically break, (like a brake line, etc.) the electronics crap out or just continue operating with less and less efficiency? Just wondering if there are any signs I should be on the lookout for.

Dave

basically, when you need etc to kick in, it doesnt. nothing physically breaks, it just stops working. at least for me anyways.

 

[Randy]

Thanks for all the ideas and input. I'll check with Bill at GBR about the front HD axles, last time I emailed him, he didn't have them yet, but that was a while back. I think I'll also wait to see how I like the stock gearing on the new tires for a little while before I decide on the gears. It sounds like some of you run much bigger tires on the stock gears with no real problems. Whichever way I go, I'll definitely decide about gear ratios before I do the diff change so it can be done at one time. Thanks for the info about the RTE springs, I'll give them a look too. I've kind of been back and forth on the winch bumper. I like the look too, but it's ~$800 for something I'm just not sure I'd utilize that much. I might put one on later. (Of course, the first time I'm grill deep in mud and I complain about trying to fetch the winch cable from under my stock bumper, you can all say "told you so!" ) I'll also give some consideration to putting a locker in back instead of the TT. Although, it sounds like if I just do the TT's front and rear, I may not need the HD axles.

Thanks again!

Dave

1) If you get the HD rear axles then go right to the locker in the rear. The only reason not to go to a full locker is the axle strength.

2) Get the 4.11s if you are increasing tire size. Despite what a few people have said, gas mileage doesn't really change much because of all this, it APPEARS to change when you put larger tires on because the rolling distance is changed. Stock DII tires are 29" in diamter, 265/75s are 31" and 255/85 are 33". Therefore you travel further per revolution of the tire. This will show up as an apparent reduction in the number of miles travelled overall unless you have the speedo recalibrated. Therefore it will appear that the 20 gallon fill-up doesn't go as far as it did before, but in reality it is only very slightly reduced by the weight increase to the truck and the additional power needed to roll the heavier tires. I think the 31" will appear to reduce mileage by 12% and the 33" by 18% ?? I can't remember the actual numbers. Regardless you will NEVER regret going to 4:11s.

3) HD front axles aren't really needed. You might want to consider HD CVs in the front once a suitable one is decided on. There are still alot of issues with these.

4) I've not had any issues with ETC....however, brake related dash lights have been on since the spring. (ABS/ETC/HDC) but they all still work. There is an issue related to CDL engagement and ETC. If you engage CDL with the truck off, ETC will be disengaged when you start it up. If you engage CDL with the truck already running ETC will remain active. There is a kit you can install to override that process.

5) GBR rocks!! Bill is great to talk to and will guide you thru the minefield.

Randy
'99 DII
GBR diffs with 4:11s; TT Front; Detroit Rear; HD rear axles; GBR front and rear driveshafts; RTE front bumper with warn 9.5ti; Greg Davis Rear Bumper; Southdown diff guards; scorpian tank guard; RTE steering guard; and a bunch of other gourmet shit too.