KieserWillys overdrive

decal

 

Thanks Twin2, where did you get that decal?

 

RJ
http://www.bearcreeksurvey.com/NOSRepro.htm

 

Might get a tachometer, this way you see what the engine rpm is at.

For longest time I was shifting too early, just because everything was so loud on the jeep. I learned the shift points by looking at sites like novak adapt in the gearing section. I figured out what RPM the engine should be with the corresponding gear, tire size and ratio.
For example, with the v6, 31's, T14 transmission, and 3.73 gears in my jeep. I normally shift around 22 mph, which about 2757 RPM which is surprising to be that the first gear is so long.
By continuing on that logic, I can figure I can stay in 2nd gear and have 2929 RPM, this will yield a speed around 45. I feel a tach would give you the best idea of speed, because you know when the RPM is too much for the engine. Speedometers are sometimes off, tires swap, dirty cables or they don't work.


I don't trust my phone for GPS speed just because the directions function thinks I am in the lake.... when I am at the house. Therefore, I don't trust my phone. This is just me, I probably broke my phone or something.


Edit: I think I will take my tachometer comment back, it seems to be problematic for a lot of people. Some claim accuracy issues when I was searching the forum.

 

Thank you guys for all the info and input on this issue. I think I will just have to drive it this way for a little while until I can look into the t case, I should've had it rebuilt when the transmission was done. Would've been a lot easier that way.

 

The intermediate shaft replacement isn't a big deal. Drop the pan, pop the shaft out, drop the gear, install new bearings and thrust washers, and install the new shaft.

 

Thank you flatyfreek, so you think this may be my issue with how fast I can go, or will it just correct the whining?

 

Your go-fast issue needs to be evaluated with a tachometer and a correct speedometer. A pace car can be used to record mph while you record rpms. A hand held tune-up tach could be used. Right now you are basing your max speed on the noise your drive train is making. Without getting accurate speed figures you are doing nothing but guessing you have a problem.

 

Gotcha, first step install tachometer.

 

But I do think I have a speed issue somewhere, even if I'm not getting an accurate reading on the speedometer and GPS. I know I'm not going 55-60 mph like I think I should.

 

Or do it with math. Roll the jeep forward one engine revolution in high gear and measure the distance travelled. See how many times that distance divides into one mile. At 60mph that is your rpm.

 

No top, but yes, i do have oil in both the t-case and tranny. And it doesn't really start whining loud until I start approaching higher speeds in 3rd gear.

 

These D18 transfer cases will always make some whining noise at cruising speed even when in good shape.
The difference between a normal whine and a loud whine indicating problems is kind of subjective. I can kind of describe the difference as a 'raspy' quality to the noise, and sometimes there may be a significant difference between the noise under forward load and coast or deceleration. Does is get really loud and nasty sounding when you let off the throttle?

If so, you may need to do the intermediate gear shaft and bearings repair. It is a fairly easy job and not very expensive as other respondents have noted.

Don

 

No Don, it does not get noisier when letting off the gas pedal. So aside from the noise, any explanation as to why top speed is only 45-50 mph? Is it possible that the t-case is just geared that way, more for torque than speed? Remember I have a T86AA with the Dana18, 3.73 gears Dana 44 rear and Dana 27 front.
Do I have to take the t-case down to change the shaft, or is it best to just open it up and check the whole thing out?

I plan on installing a tach as suggested hopefully tomorrow to get an idea of the rpm's

 

Seems like you would start with diagnosing the engine. Maybe your timing is way off and you just aren't getting all the V6 has to give. If lack of power is the culprit, start with the engine. A lot cheaper and easier than pulling the t-case apart. Also, while not terribly difficult, replacing the intermediate shaft and bearing with the t-case still in the vehicle is not a walk in the park. It is awkward and demands some patience to get all the rollers to stay in place while you insert the shaft. But all that aside, make sure your engine is running well before you start with the t-case. Just my .02

 

Thanks posimoto for the heads up on the engine. It starts up fine, runs good, nice and smooth. No sings of the timing being off, however, I'm sure checking that out won't hurt.

 

RJ........first off you not dealing with a motor that has a bunch of Horsepower , maybe at best 155......and the nose and windshield on that Jeep is like trying to push a Barn Door down the freeway.........couple that with 3.73 final drive ratio with your 215/75r and the motor is only spinning at about 1965 RPM's at 45 MPH........at 65 MPH the motor would be near 2838 RPM's..........what I am trying to say and this is with experience with these little motors is that the aerodynamics of the Jeep coupled with a "Tall Gear" like you have is not even close to getting that little V6 into it's sweet spot RPM wise! That coupled with the normal heavy 55 lb flywheel and your just not going to get that forward drive to accelerate that package. Of course that would be with a motor that is properly tuned and making the correct Horsepower.

The first I would do is run a compression and or a leak down test on each cylinder just to see what condition the engine is in..........If it checks out OK I would go find a long grade somewhere whereby you can use the slope down hill to your advantage and see if that little rascal will see 60 mph...........if it does now you know the answer.

 

Thanks terry99,

i had the compression checked by a mechanic already and it checked out good on all cylinders. I plan on checking the timing and installing a tach this weekend, since the advice is to start with the engine.
i understand about lack of horsepower and gears, which I can accept as the reason why I don't have a good top speed. Which leads me to my original question of adding an overdrive to give me a little more speed, however, there have been some on this thread that say I should be going fast with no issues with the engine, transmission, t-case and gears I have. This of course started the whole discussion of something possibly being wrong with the t-case since is was not rebuilt when the transmission was since it was making a whining noise.

I do appreciate all the advice and information from the more knowledgable and experienced jeepers. Who have pointed out that, yes I do have an issue somewhere, just have to find it. I will start with the engine first.