727 to Getrag swap

[RSchwarzli]

dpuckett



I'm sure my truck could go over 80 if I matted it, but the thing is just crying. As for your mom's going 70 in 3rd, that is not the question, but more what is the rpm at that speed?



bgilbert



If I did get it to go to 80, I am back to the original issue, the really high rpm's (which you know how loud that is). The big issue is I will have about a one hour commute and that long at that rpm would make me def. Not to mention the cops wanting to pull me over after I get the stacks on.



Robert



P. S. You'le have to speak up my boy, I'm hard of hearin!

 

[1stgen4evr]

727 to Getrag

With FWD, either stay with what you have or skip the getrag and get a 4500. The comments regarding the getrag in fwd trucks are not favorable. I am very satisfied with mine in a TWD 93 dually and I also have two automaitc ODs all TWD. I have driven an 89 with the 727 and 3:07 ratio. It is slow compared to the OD automatic or manual. There is bolt on equipment for the Getrag or the 4500 or the automatics. You will likely have to change a drive shaft. There is enough help on the forum to do whatever you decide.



Cheapest thing would be to put the tallest tires you can stand to look at on the truck. We put 19. 5s on a fwd GMC conversion to get the engine speed down.



1stgen4evr

James

 

[rvaughn801]

You are not getting full travel on your injector pump. My 89 with 727 will run an indicated 84 MPH flat out on level ground. Either the floor mat is in the way, or the rod that actuates the pump needs adjustment (bend it). I routinely run my truck on the floor for hours, with absolutely no problems. My truck averages 22 MPG. The cruise can only open the pump enough for 62 MPH, my foot has to do the rest. Has anyone figured out how to get the cruise some more OOOMPH?

 

[1stgen4evr]

engine speed

As noted, the engine will turn on up. It just sounds like it is turning to high to me. If you can stand the sound, it is probably alright. We have some engines from spotter trucks that were run full throttle all the time. They have in the range of 10k hours and are still in running condition. So the engine will take it.



Again, if you are going manual, skip the Getag. You will like the 518 but don't even think about using the computer. Add the OD control on the shift lever.



There are trucks in the classified that can be bought pretty cheap. Before you get into all the swapping, consider owning two trucks for a while. Sell the one you like the least. You will have a truck to drive all the time and about the same money overall in the end.



I think that the general cost of going to a manual would be in the range of two thousand by the time you finished. For the 4500 closer to 3 thousand. You could probably get into a 518 for 18 hundred. You can get a whole truck for 3k if you look a while.



If you still like working on trucks, and don't count your time, it doesn't matter which way you go. I have tired of mechanical repair and would rather trade than do all the stuff. Even at that, I have a project going right now.



On the cruise control. Cut a stick that can be used to prop the pedal smack to the floor. Fix it so that you can tip it out with the toe of your shoe. It could get you killed though.



1stgen4evr

James

 

[RSchwarzli]

What happens to a getrag in a 4wd that doesn't happen in a 2wd that makes it such a bad idea?



Richvaughn,



I will admit it so everyone knows, "I have never put the pedal on the floor on flat ground. " In saying that, I really could not tell you how fast my truck will go although my guess is it will do 80 wide open. My issue is not that the truck won't go fast enough (Well, that is not entirely true, 11 sec quarters would be nice ). My issue is that by the time I get to that speed (being 70 or 80) the rpm is so loud it hurts the ears after an hours drive. Also I am hesitent to install the stacks for fear of how loud it will be driving into the city at highway speed. The bottom line I guess is that I can't stand the sound of it, so something has to be done.



Robert

 

[phillips5]

The od addon goes behind the trans to speed up the rear driveshaft BUT NOT THE FRONT SHAFT big problems if you fourwheel in od.

 

[1stgen4evr]

What happens to a getrag in a 4wd that doesn't happen in a 2wd that makes it such a b

Nothing in and of itself. It is the application and the way that it is used. If you only used the truck as twd and never rode it hard, I think you could get as good result as I have. 404k miles on my Getrag. But the four tires on the ground can effectively tie the running gear to a rock and the Cummins can then over torque the Getrag to the point that it will fail. Too many fwd owners use their trucks right to the limit of the engine and in that mode, the Getrag just isn't enough. Some with really big HP can attest that the 4500 or 5600 can be destroyed. I bought a 4500 that is dead from lack of lube. It won't matter what transmission you use if you let it run out of oil, it will roast.



That is the reason I say to skip the Getrag and go to the 4500 or 5600. You will like the overdrive on any of the choices. If there is a Getrag available in the price range of 500, go for it.



I still say that you can buy a second truck for the amount of money you will eventually spend on a conversion.



1stgen4evr

James

 

[dpuckett]

Ok, I jumped the ugn a little. nothing new. I would assume (here I go again, setting myself up) that since it was a stock rebuild, that it is turning in the neighborhood of 2800RPM. Now, if your will do 80, or thereabouts, and it is just too loud, there are a few things you can check. 1) Is there any soundproofing/ deadening stuff in or around the cab? 2) How is your muffler situation? Straight pipe will make it LOUD at higher RPM. 3) Timing could be off a bit- it will rattle and make noise if it is either too fast OR slow; been each way, no fun, either way. Since we're under the hood, valves will rattle at higher RPMs, as well. Or is it just the nice roar of a Cumins working that gets to you? I'll admit, mine isnt a whole lot of fun at 70 mph; esp since I have a defective muffler, and no pipe past the fuel tank.



NOw, as for a Getrag in a 4x4, I personally have had no troubel with them, and I've had 2 4x4s; 3 4x2s. IF you keep them a quart overfull, preferrably synthetic, and IF you dont lug the cr@p outta them, they should do ok, unless you do extreme off roading, or tow super heavy- I mean like 25K+ GCVW. I have seen them go 600K, and puke at 80K. Same with the NV4500- knew a guy who lost his 5th gear at 50K, and got it rebuilt under warranty.



Daniel

 

[RSchwarzli]

dpuckett,



1) O. K. mabee I am slow, but who's rebuild are you speaking of yours or mine?



2) As for insulation I have a fair layer of it under the carpet.



3)The exhaust pipe is not great on the last quarter of it, but it is not really heard in the cab. I am not so worried about the exhaust noise as adding strait stacks when I have time would be stupid if I was. Oo.



4)As for stuff ratteling there is nothing that I can find or hear. The main thing is just the roar of the engine, which as you said, at 70 mph for long periods of time is not fun.



5) As for towing the most that I see that I would be towing is a car or tractor on a trailer so I don't think that would be to hard on the trans.



Thanks

Robert

 

[bgilbert]

Robert sounds like you need a new pilot injected 03 and up. You've probly seen the sticker 'real trucks rattle', well thats the nature of the beast. If you really want to quiet a 1st gen, remove the seat, carpet and have a spray in sound deadening material sprayed on the firewall and floor etc, then add more rubber type sound deadening material or any kind for that matter, then insulation, carpet AND interior plastic molding on kick panels and throughout. My 91 LE has carpet and plastic molding and is quieter than my 89 was even before the stacks and WOT against the governor vs the 89 same rpm but no carpet or molding etc. Oh and a muffler might quiet the truck too. . Bill-looking for an 8" stack so my truck can be louder!

 

[RSchwarzli]

Thanks to all for your time, help, and patiance. It is very much appreciated. It seems that with having to change so many things I had not thought about, especially the transfer case, that I am best off to live with what I have for now and at some point do it right and just get the NV5600. Thanks again for all the help.



Robert

 

[CGauthier]

I want i want i want i WANT the NV5600 too, my truck is going to be used alot for towing approx. 17k lbs and then some, butt i definitely do not have the money now, and will probably never have the money until tha Getrag pukes on me; then i will have to take out a mortgage i guess Now i no there are different years and models of trannys and some are better than others, but any1 got any ideas as to how much a guy could get away with dishin out to get one of these 6-speeds that i want SO much into tha truck ready 2 go? And, i will never take an older one with known problems in order to save a buck... . Do it right the first time

 

[rvaughn801]

I understand the issue is more noise than worrying about the Cummins coming apart. With the muffler gone, I still think I get more engine roar than exhaust noise. I hear the exhaust when the back or passenger window is open. I am sure other drivers hear it all the time .



I do think it says something about the CTD that with over a quarter of million miles on the clock I can still run it for hours at or near the floor mat. It is engineered and over built, and represents a great value.



Unless I have something to haul or just want to listen to the rattle I drive a '95 Chevy Wagon on long trips. The LT1 engine turns 1600 RPM at 75 MPH, and gets almost as many MPG as the CTD. If I could afford it, I would get a new CTD with a quad cab and a 6-speed. But until then, I will get by with the reg cab '89. I'm still not going to make a stick to hold the throttle to the floor, though. Good luck with your truck.