| Author | Message | ||
| Patrick Wallace (Phwallace)
Registered Member Username: Phwallace Post Number: 1 Registered: 8-2008 Posted From: 216.145.195.105 Rating: N/A |
hello all, I am brand new to this. The production company that I co-own just bought a new to us 1968 PD-4093 that has been converted into a standard rock and roll tour bus. Long stories involved, the bus needs to have the engine pulled and some pretty major work done to it. There is a question about if it's possible to convert the bus to an automatic transmission at this time since we saw in the research that later models came as automatics. The bus has a Detroit 8V71 and is currently, according to the seller, hooked to the factory transmission, a 4 speed, solenoid reverse- serial number T-1055257. The seller told me it's an Allison, but I'm seeing some indication in manuals it may be a Spicer? So, any ideas or help would be greatly appreciated. I'm located about an 1 1/2 hours west of Washington DC in Martinsburg, WV, so if there are people local to me that you can recommend I get to know for parts/expertise/good beer, I'd love to know. Thanks so much for any help you can offer and I'm working my way though the previous posts, so if this has already been answered, I'm very sorry, but in the meantime, I'm learning about about the bus we bought. | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 828 Registered: 12-2000 Posted From: 76.3.173.51  Rating: |
Patrick, An allison 730 auto transmission wll fit in your bus. I cut & pasted this from the Yahoo GMC bus group. Looks like perfect timing, this guy has a GM auto Transmission he needs to get rid of. His phone number is at the bottom. Jack Hello All Started yesterday to strip tranny to sell for scrap. went in from driveshaft end. As soon as I opened it up I saw how clean it was in the inside. Checked out a few clutch plates. They are new, so the preson I bought the bus and extra transmission from said tranny was rebuilt told the truth. I put the tranny back together because I can't bring myself to ruin a perfectkly good rebuilt tranny. I just need it out of my way,please someone make offer. Mike 4903-027 Miami,FL 305-632-2008 (Message edited by JackConrad on September 03, 2008) | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 545 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
Pat, Me and Jack both own MCIs, which have a totally different drivetrain than a GMC, but a whole bunch of the requirements for a changeover are the same. In addition to the V730 trans, you will need a shifter, an SAE #1 flywheel, some type of trans cooler, either an oil-to-air cooler, or a dual cooler replacement for the single lube oil cooler presently on the engine. Then, modulator linkage between the governor and trans. Differential ratio might also be an issue. I'm not qualified on GMs, but I think you might have to do some cutting. There are several qualified GM owners here who have done this, and I'm sure you will here from them on exactly how! Welcome, and good luck, George | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 546 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
Another thought, The new classified section here has the engine and trans you need, which would instantly resolve the flywheel, cooler and shifter issues. Not to mention not having to do major engine work on yours? After doing a little more looking, it may be sold, but its worth a call. FWIW, George (Message edited by George Mc6 on September 03, 2008) | ||
| J.L.Vickers (Roadrunnertex)
Registered Member Username: Roadrunnertex Post Number: 42 Registered: 10-2006 Posted From: 76.1.93.255 Rating: N/A |
Let a GMC owner step in who had been there and done that. Call Nimco at 1-800-526-8055 as for Nick Liberti. Nick can sell you the complete kit to do your change over including instructions on the modifications you will have to do. The change over will make the bus a lot easier to operate. The transmission you have in your coach is a Spicer 4 speed model 7145K jlv | ||
| J.L.Vickers (Roadrunnertex)
Registered Member Username: Roadrunnertex Post Number: 43 Registered: 10-2006 Posted From: 76.1.93.255 Rating: N/A |
Typo on the transmission model # sorry it should read 7145VK | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 457 Registered: 10-2006 Posted From: 208.100.193.93 Rating: N/A |
The problem with installing a 730 in a GM is the lower top speed and loss of fuel milage. If you don't mind a slow bus that gets 6? mpg , feel free. But its a huge hole to chop in the bulkhead that will need excellent reinforcing. The other tranny that fits is the VS series. These are great for speed and fuel milage , but hill climbing (western) requires great patience , and both require a tranny cooler. Most folks will find it easier , and more rewarding to swop coaches , instead if converting , tho it has been done. FF | ||
| Bill Gerrie (Bill_gerrie)
Registered Member Username: Bill_gerrie Post Number: 184 Registered: 3-2006 Posted From: 209.50.72.2 Rating: N/A |
Patric George mentioned the solution you need. So much easier to buy the complete package. You need a left hand turning engine with a V730. You will lose a bit on the fuel mileage and top speed but easier to drive. I have done a tranny switch on at least three different GM coaches and no problems. Bill | ||
| Patrick Wallace (Phwallace)
Registered Member Username: Phwallace Post Number: 2 Registered: 8-2008 Posted From: 216.145.195.105 Rating: N/A |
Guys, thank you so much for all the information. We've been told the bus is currently getting around 11 MPG, so going to 6? would be a drop but we don't have this for long touring, more going to a place and staying for a week while we run a fair, etc. Plus, as you all know, it's just cool to own a bus. I'll start placing some calls from the looks of things. | ||
| Arthur N. Gaudet (Runcutter)
Registered Member Username: Runcutter Post Number: 12 Registered: 9-2006 Posted From: 76.185.242.7 Rating: N/A |
Patrick, I have a 4107, essentially the same as a 4903 but five feet shorter - thus somewhat lighter. On one long trip, I my MPG was in the high nine/low 10 range. With a few decades in the bus business, I drive pretty conservatively. Thus I'd be pretty suspect of an 11 MPG claim - unless the driver was quite conservative (55mph, anticipating traffic signals, etc. Now, back when I was driving (and instructing on) 4903's and 4905's in service, the stick shift was not a problem. The driver becomes the "automatic" part of the transmission. Learning curve, yes - but I only had one student that I couldn't teach (or he couldn't learn). So, it may be worth asking whether a change-out to an automatic ($) is worthwhile, or whether you'd do better to learn to double-clutch (hint, it's not really that hard). One additional caveat - we take our coaches into places that they would seldom see in service. One fellow who used to be active sold his stickshift 4106 and bought an automatic 4108, in part because he had steep driveways in some of the places he went - and our high-ratio first gear doesn't like steep takeoffs - hard (costly) on the clutch. If you can, post the serial number of the coach (PD-4903-xxxx), JLV can find the original owner - and I'm curious as to whether any of my old friends are still around somewhere. Also, if you want to go further, the Ohio Museum of Transportation can provide a copy of the delivery configuration, straight from GM, for a nominal contribution. Arthur (Message edited by runcutter on September 04, 2008) | ||
| Frank Allen (Frank66)
Registered Member Username: Frank66 Post Number: 91 Registered: 10-2005 Posted From: 64.12.117.73 Rating: N/A |
putting a automatic in your bus will make it easy to drive, the downside is it will drop the mpg 1.5 and the top speed about 15 to 20 mph, the engine will also run a bit hotter especally on a climb. this is what i experienced. had i done my homework a bit better i would have never done it just an opinion Frank Allen 4106 | ||
| Dan West (Utahclaimjumper)
Registered Member Username: Utahclaimjumper Post Number: 101 Registered: 1-2005 Posted From: 208.66.38.60 Rating: N/A |
I installed a VS2-8 and lowered the rear end ratio a bit to compensate for the OD, I like the performance and the mileage.>>>Dan ( no cutting the bulkhead needed) | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 460 Registered: 10-2006 Posted From: 208.100.193.11 Rating: N/A |
" We've been told the bus is currently getting around 11 MPG," 8 mpg is probably closer on the flats. FF | ||
| Patrick Wallace (Phwallace)
Registered Member Username: Phwallace Post Number: 3 Registered: 8-2008 Posted From: 216.145.195.105  Rating: N/A |
For Arthur- We have the original sales slip to Red Arrow Lines of Upper Darby, PA on 6-17-68 Frame number 174 Sales order #-191144 It looks like it did time on this line until the mid 1980's then when to a church group, then to a rock band, then to us. The church group did the primary conversion and they meant well, but... Again, thanks guys for all the information....I grew up driving split axle (maybe only an Ohio term) early 60's farm trucks, so double clutching is no issue for me, but right now, I'm the only one that can drive the bus right now. Hence the thought about the auto. For the deal we got on the bus, the motor/tranny work is worth it (to a point) especially if we can get a few more years of solid use out of the girl. |
